2. [ELEX]

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In a circuit, an active element is one which A. Supplies energy B. Receives energy C. Both supplies and receives energy D. Amplifies signal

In a complex number 5 + j 10, 10 is called part. A. Imaginary B. Real C. Conjugate D. Integer

604. The diameter of the atom is about ___________. A. 10^-10 m B. 10^-8 m C. 10^-2 m D. 10^-15 m

404. The circuit admittance Y = 0.2 - j0.6, the circuit is A. resistive B. inductive C. capacitive D. reactive

407. What is the resonant frequency of a circuit when L of 3 microhenry and C of 40 picofarad are in series? A. 1.33 MHz B. 14.5 MHz C. 14.5 kHz D. 1.33 kHz

600. An electric water heater has a rating of 1 kW, 230 V. The coil used as the heating element is 10 m long and has a resistivity of 1.724 x 10^-6 ohm-cm. Determine the required diameter of the wire in mils. A. 2.43 mils B. 2.52 mils C. 3.21 mils D. 1.35 mils

. A gang capacitor is a variable capacitor in which capacitance is varied by changing the A. Dielectric B. Number of plates C. Plate area D. Distance between plates

. Two capacitors of capacitance 9 µF and 18 µF in series will have a total capacitance of A. 27 µF B. 162 µF C. 6 µF D. 180 µF

745. If switch S1 is open and switch S2 is closed in Fig. 15.14, then circuit resistance will be _________ electrical circuit figure 15.14 A. 1200 ohms B. 1000 ohms C. 1400 ohms D. 2400 ohms

855. The value of IN in Fig. 8.2(b) is _________. electrical circuit figure 18.2 A. 3 A B. 1 A C. 2 A D. none of the above

A 0.09 microfarad capacitor is charged to 220 volts. How long in milliseconds will it discharged resistor has a resistance of 20,000 ohms? A. 1.5 B. 2.5 C. 1.25 D. 0.5

. If three 100-pF capacitors are connected in series, then the total capacitance is A. 300 pF B. 100 pF C. 50 pF D. 33.3 pF

334. Find the current that flows through the filament of a 400 watts flat iron connected to a 220 Volt power line. A. 50 mA B. 5 A C. 5 mA D. 500 mA

400. Calculate the total impedance of a parallel RC circuit if R = XC = 50 Ω. A. 25 @ 45° Ω B. 25 @ -45° Ω C. 35.35 @ 45° Ω D. 35.35 @ -45° Ω

885. Thevenin resistance Rth is found A. between any two "open" terminals B. by short-circuiting the given two terminals C. by removing voltage sources along with their internal resistance D. between same open terminals as for Vth

.How many degrees of phase represents one full cycle? A. 360 B. 180 C. 270 D. 90

313. An electronic/electrical component/device used to store electrical energy. A. Capacitor B. Inductor C. Resistor D. lightning arrester

317. If two micro-farad capacitors are connected in series, what will be the total effective capacitance? A. 0.125 microfarad B. 0.0624 microfarad C. 2.5 microfarad D. 0.50 microfarad

320. A coil of wire wound, with or without a magnetic core designed to have a higher self-inductance than a straight wire. A. Inductor B. Solenoid C. Toroid D. Inductive relay

324. An electronic device draws 300 watts from its 24-volt power source. Find effective resistance. A. 1.92 ohms B. 19.20 ohms C. 1.25 ohms D. 12.50 ohms

326. Two resistors, 10 Ω and 100 Ω are connected in parallel, approximately, what is the total resistance? A. 10 Ω B. 50 Ω C. 90 Ω D. 100 Ω

333. If 12 V are applied to a circuit that consumes 78 W, what is the current flow through the circuit? A. 6.5 A B. 936 A C. 0.15 A D. 9.36 A

335. An electrical device has a resistance of 10 Ω and is supplied with a 5 ampere constant current source. If the deice is rated 100 Vdc, determine its power consumed. A. 250 W B. 450 W C. 750 W D. 1000 W

336. The power dissipated by a 10 Ω load resistor with a current rating of 5 amperes is _________ if supplied with a 20 volt dc potential. A. 40 W B. 80 W C. 160W D. 250 W

340. What theorem we should use in solving electrical circuits with several voltage sources? A. superposition B. Norton C. Thevenin D. Kirchhoff

342. The sum of all currents entering a junction is equal to the sum of currents leaving away from that junction. A. Kirchhoff's first law B. Kirchhoff's second law C. Norton's theorem D. Thevenin's theorem

345. A certain Thevenin equivalent circuit has parameters RTH = 10 Ω and VTH = 20 V. If this is converted to Norton's equivalent circuit, RN and IN would be A. 10 Ω and 2 A B. 10 Ω and 4 A C. 0.10 and 2 A D. 0.10 and 4 A

349. In a network, what do we call a reference point chosen such that more branches in a circuit met. A. node B. junction C. ground D. mesh

352. Mesh analysis is best used together with what circuit law? A. KVL B. KCL C. VDT D. CDT

360. An ac-voltage has an equation v = 240 sin120πt, its frequency is A. 60 Hz B. 90 Hz C. 120 Hz D. 240 Hz

365. If an alternating voltage has a magnitude of 10 V at 30°, what is its maximum voltage? A. 20 V B. 30 V C. 40 V D. 50 V

381. A series circuit consists of an 80 mH inductor and a 150 μF capacitor. Calculate the total reactance if it is connected to a 220-volt 60-cycle source. A. 12.5 Ω inductive B. 12.5 Ω capacitive C. 47.8 Ω inductive D. 47.8 Ω capacitive

385. What will be the current equation in a series RC network if supplied with v = Vmsin120πt source. The circuit has a power factor pf = 0.5? A. i = Imaxsin(120πt + 60) B. i = Imaxsin(120πt - 60) C. i = Imaxsin(120πt + 30) D. i = Imaxsin(120πt - 30)

386. The power factor (pf) of a series LC circuit is A. 0 B. 0.5 C. 0.75 D. 1.0

391. A 6-Ω resistor is connected in series with a capacitive reactance of 8 Ω. If the supply voltage is 200 V, what is the power consumed by the circuit? A. 2400 W B. 4000 W C. 5000 W D. 6666.67 W

397. What is the total impedance of a series circuit consisting of R = 6 Ω, XC = 8 Ω, and XL = 16 Ω? A. 10 Ω B. 14 Ω C. 24.73 Ω D. 30 Ω

401. A 100-volt source is supplying a parallel RC circuit having a total impedance of 35.35 Ω. Calculate the total line current. A. 2.83 ∠ 45° B. 2.83 ∠ -45° C. 4.00 ∠ 45° D. 4.00 ∠ -45°

406. If you need an LC circuit to be resonant at 2500 Hz and use a 150 mH coil, what should the capacitance value be? A. 0.027 μF B. 0.015 μF C. 0.15 μF D. 27 μF

409. A series circuit at resonance would mean, the circuit is A. resistive B. inductive C. capacitive D. reactive

413. A parallel circuit at resonance would mean, the circuit is A. resistive B. inductive C. reactive D. capacitive

423. Refers to a reactive power. A. Wattles, non productive power B. Power consumed in circuit Q C. Power loss because of capacitor leakage D. Power consumed in wire resistance in an inductor

467. At what frequency will an inductor of 5mH have the same reactance as a capacitor of 0.1 µF? A. 7.12 kHz B. 7.12 Hz C. 7.12 MHz D. 7.12 Ghz

475. A DC voltage of 80 volts is applied to a circuit containing a resistance of 80 ohms in series with an inductance of 20 Henry. Calculate the growth of current at the instant of completing the circuit. A. 4 A/s B. 2 A/s C. ½ A/s D. ¼ A/s

486. A circuit consisting of 20 ohms resistor, 20 mH inductor and a 100 microfarad capacitor in series is connected to a 200 V DC supply. The capacitor is initially uncharged. Find the maximum instantaneous current. A. 6.45 A B. 7.45 A C. 8.45 A D. 9.45 A

599. Determine the length of a copper wire (ρ = 10.37 Ω-CM/ft) where diameter is 0.30 inch and resistance of 0.5 Ω at 20°C. A. 4,339 ft B. 5.225 ft C. 6,125 ft D. none of these

609. If the number of valence electrons of an atom is less than 4, the substance is usually __________. A. a conductor B. an insulator C. a semiconductor D. none of these

611. If the number of valence electrons of an atom is exactly 4, the substance is usually _________. A. a semiconductor B. an insulator C. a conductor D. a semiconductor

612. The number of valence electrons of an atom is less than 4. The substance will be probably __________. A. a metal B. a non-metal C. an insulator D. a semiconductor

615. Electric current in a wire is the flow of _________. A. free electrons B. bound electrons C. valence electrons D. atoms

623. The specific resistance of a conductor _________ with rise in temperature. A. increases B. decreases C. remains unchanged D. none of these

627. Conductors have ________ temperature coefficient of resistance. A. positive B. negative C. zero D. none of these

628. Semiconductors have ________ temperature coefficient of resistance. A. negative B. positive C. zero D. none of these

633. Fig. 13.1 shows the temperature/resistance graph of a conductor. The value of α0 is ________. A. 0.005/°C B. 0.004/°C C. 0.1/°C D. 0.4/°C

635. Referring to Fig. 13.2, the value of α0 is ________. A. 1/30 per °C B. 1/40 per °C C. 1/1200 per °C D. none of these

636. Referring to Fig. 13.2, the value of R40 will be ________. A. 70 ohms B. 40 ohms C. 35 ohms D. 50 ohms

639. The value of α50 of a conductor is 1/230 per °C. The value of α0 will be ________. A. 1/180 per °C B. 1/280 per °C C. 1/250 per °C D. none of these

641. Two wires A and B have the same cross-section and are made of the same material, RA = 600 Ω and RB = 100 Ω. The number of times A is longer than B is A. 6 B. 2 C. 4 D. 5

646. Carbon composition resistors are most popular because they A. cost the least B. are smaller C. can withstand overload D. do not produce electric noise

650. The charge delivered by a constant voltage source is shown. Determine the current supplied by the source at (a) t = 1 s (b) t = 3 s. A. 5 ma, -3.33 ma B. 5 ma, 3.33 ma C. -3.33 ma, 5 ma D. 3.33 ma, 5 ma

652. EE April 1981, October 1984 Two (2) 115-V incandescent lamps A and B are connected in series across a 230-V source. If lamp A is rated 75 watts and lamp B is rated 50 watts, determine the current drawn by the series connection. A. 0.52 A B. 0.64 A C. 0.48 A D. 0.57 A

654. REE Board Exam March 1998 Three resistors of 10, 15 and 20 ohms each are connected in parallel. What is the total conductance? A. 0.217 siemens B. 3.41 siemens C. 4.52 siemens D. 0.562 siemens

655. REE Board Exam October 1997 A 5-ohm resistance is connected in parallel with a 10-ohm resistance. Another set, a 6-ohm and an 8-ohm resistances are also connected in parallel. The two sets are connected in series. What is the equivalent resistance? A. 6.76 ohm B. 9.25 ohm C. 14.4 ohms D. 21.2 ohms

656. REE Board Exam March 1998 Two resistances of 10 and 15 ohms each respectively are connected in parallel. The two are then connected in series with a 5-ohm resistance. What is the equivalent resistance? A. 11 ohms B. 12 ohms C. 10 ohms D. 9 ohms

661. REE Board Exam September 2000 Two 10-Ω resistances are connected in parallel. The two are then connected in series with a 5-Ω resistance. It is then connected across a 24-volt battery; find the voltage across the 5-Ω resistor. A. 12 volts B. 24 volts C. 9 volts D. 15 volts

663. REE Board Exam September 2000 How many abvolts in 1 volt? A. 10^8 abvolts B. 10^-8 abvolts C. 1 abvolt D. 10 abvolt

664. REE Board Exam September 2003 A total current of 60 A is divided among 3 parallel branches having resistances of 10 Ω, 6 Ω and 12 Ω, respectively. What is the current that flows through the branch with 10 Ω resistance? A. 17.1 A B. 28.6 A C. 14.3 A D. 42.9 A

666. ECE Board Exam November 1998 The theory of Ohm's law is applied in a _________ circuit. A. linear B. exponential C. trivalent D. unilateral

675. ECE Board Exam November 2000 A circuit which a break exists in the complete conduction pathway A. Open circuit B. Short circuit C. Close circuit D. Circuit

684. ECE Board Exam November 1997 Other factors remaining constant, what would be the effect on the current flow in a given circuit if the applied potential were doubled? A. It would double B. It would increase 4 times C. It would remain the same D. It would be decrease by ½

688. ECE Board Exam November 1999 A 33 kilo ohms resistor is connected in a series parallel combination made up of a 56 kilo ohm resistor and a 7.8 kilo ohm resistor. What is the total combined resistance of these three resistors? A. 39067 ohms B. 49069 ohms C. 63769 ohms D. 95800 ohms

692. ECE Board Exam April 1998 If 12 V are applied to a circuit that consumes 78 W, what is the current flow through the circuits? A. 6.5 A B. 936 A C. 0.15 A D. 9.36 A

705. The hot resistance of an incandescent lamp is about ________ its cold resistance. A. 10 times B. 2 times C. 100 times D. 50 times

710. Inductance and capacitance are not relevant in a d.c. circuit because __________ A. frequency of d.c. is zero B. it is a simple circuit C. they do not exist in a d.c. circuit D. none of the above

724. If a d.c. supply of 180 V is connected across terminals AB in Fig. 15.5, then current in 6 ohm resistor will be _________. electrical circuit figure 15.5 A. 10 A B. 5 A C. 12 A D. 6 A

726. The resistance across terminals AB of the circuit shown in Fig. 15.6 is ________ electrical circuit figure 15.6 A. 4 ohms B. 18 ohms C. 34 ohms D. 8 ohms

731. The voltage across the parallel circuit shown in Fig. 15.8 is ________ electrical circuit figure 15.8 A. 15 V B. 10 V C. 30 V D. 12. 5 V

771. EE Board Exam April 1992 An electric heater carries 12 A at 110 V, is submerged in 22.5 lbs of water for 30 minutes. What will be the final temperature of the water if its initial temperature is 35°F? A. 135.43°F B. 125.42°F C. 133.56°F D. 128.33°F

774. EE Board Exam October 1991 Four cubic meters of water is to be heated by means of four 1.5 kW, 230-V immersion heating elements. Assuming the efficiency of the heater as 90%, determine the time required in boiling the water if the initial temperature is 20°C and if the elements are connected two in series in parallel with two in series. A. 275.6 hrs B. 295.3 hrs C. 252.2 hrs D. 264.4 hrs

776. REE Board Exam September 2001 10^13 ergs/sec is equal to how many kilowatts? A. 1,000 B. 250 C. 100 D. 10

780. REE Board Exam October 1999 When heat is transferred into any other form of energy or when other forms of energy are converted into heat, the total amount of energy is constant. This is known as A. First law of thermodynamics B. Boyle's law C. Specific heat D. Isothermal expansion

781. REE Board Exam September 2002 What is 10^12 ergs/sec in kW? A. 100 kW B. 1,000 kW C. 10 kW D. 10,000 kW

808. EE Board Exam April 1989 The LRT trolley system 10 miles long is fed by two substations that generate 600 volts and 560 volts, respectively. The resistance of the trolley wire and rail return is 0.3 ohm per mile. If the car is located 4 miles from the 600 volt station draws 200 A from the line. How much is the current supplied by each station? A. 133.33 A, 66.67 A B. 123.67 A, 76.33 A C. 117.44 A, 82.56 A D. 125.54 A, 63.05 A

821. ECE Board Exam April 2000 According to Kichhoff's current law, what is the algebraic sum of all currents entering and exiting a node. A. zero B. a negative value C. the algebraic sum of all currents D. a positive value

828. A circuit contains a 5 A current source in parallel with an 8 ohm resistor. What is the Thevenin's voltage and Thevenin's resistance of the circuit? A. 40 V, 8 ohms B. 5/8 V, 40 ohms C. 5 V, 8 ohms D. 5/8 V, 8 ohms

841. In the circuit shown in Fig. 17.6, there are ________ meshes. electrical circuit figure 17.6 A. two B. three C. four D. none of these

843. To solve the circuit shown in Fig. 17.7 by nodal analysis, we require ________ electrical circuit figure 17.7 A. one equation B. two equation C. three equations D. none of these

848. In order to solve the circuit shown in Fig. 17.8 by nodal analysis, we require electrical circuit figure 17.8 A. one equation B. two equation C. three equations D. none of these

856. Thevenin's theorem is _________ form on an equivalent circuit. A. voltage B. current C. both voltage and current D. none of the above

860. In the analysis of a transistor circuit, we generally use _________. A. Norton's B. Thevenin's C. reciprocity D. superposition

862. The value of Rth in Fig. 18.3(b) is ________. electrical circuit figure 18.3 A. 3 Ω B. 2 Ω C. 1.5 Ω D. 6 Ω

870. The open-circuited voltage at terminals AB in Fig. 18.4 is _________. electrical circuit figure 18.4 A. 12 V B. 6 V C. 15 V D. 9.5 V

872. Under the conditions of maximum power transfer, the voltage across RL in Fig. 18.4 is _________. electrical circuit figure 18.4 A. 6 V B. 4 V C. 9 V D. 12 V

873. The output resistance of a voltage source is 4 Ω. Its internal resistance will be ________. A. 4 Ω B. 2 Ω C. 1 Ω D. infinite

877. According to KVL, the algebraic sum of all IR drops and e.m.f.s in any closed loop of a network is always A. zero B. positive C. negative D. determined by the battery e.m.f.s

894. Thevenin equivalent circuit of the network shown in Fig. 18.7 is required. The value of the open-circuit voltage across terminals A and B of this circuit is ________ volt. electrical circuit figure 18.7 A. zero B. 2i/10 C. 2i/5 D. 2i

A circuit whose parameters change with voltage or current. A. Non-linear circuit B. Linear circuit A. CV2 /2 C. Complex circuit D. Passive circuit

A coil of inductance L has an inductive reactance of XL in an ac circuit in which the effective current is I. The coil is made from a superconducting material. The rate at which power is dissipated in the coil is A. 0 B. I 2 XL C. IXL D. IXL

A series-parallel combination of identical resistors will A. Increase the power rating compared with one resistor alone B. Increase the voltage rating compared with one resistor alone C. Reduce the voltage rating compared with resistor alone D. Result in an expensive circuit

A term used to express the amount of electrical energy stored in electrostatic field. A. Joules B. Coulombs C. Watts D. Electron-volt

A wire of one kilometre length has a resistance of 20 n. If the length is halved, then the the new resistance is the original resistance. A. Half B. Twice C. One-fourth D. Three times

According to Gauss theorem, flux can be equated to A. Charge B. Field intensity C. Current D. Voltage

An inductor carries 2 A dc. If its inductance is 100 µH, then what is its inductive reactance? A. Zero B. 1.3 kn C. 628 n D. -628 n

Another term of the quality factor of the resonant circuit. A. Figure of merit B. Figure of demerit C. Noise factor D. Noise figure

ECE Board Exam April 1998 588. What happens to the resistance of a conductor wire when its temperature is lowered? A. Decreased B. Steady C. Zero D. Increased

ECE Board Exam November 1995 537. __________ has a unit of electron volt. A. Energy B. Potential difference C. Current D. Charge

ECE Board Exam November 1998 542. Resulting effect when electron is made to move A. dynamic electricity B. static electricity C. lines of force D. magnetic lines

ECE Board Exam November 1998 581. What is the value of a resistor having the following colored bands: Yellow-Gray-Red-Silver? A. 4800 ohms ±10% B. 480 ohms ±10% C. 3800 ohms ±1% D. 4.8 ohms ±1%

ECE Board Exam November 1999 529. The lightest kind of atom or element A. hydrogen B. helium C. titanium D. oxygen

ECE Board Exam November 2000 567. The ability to do work A. energy B. kinetic C. potential D. voltage

ECE Board Exam November 2001 551. The new and preferred term for conductance or mho A. Siemens B. She-man C. Seaman D. ROM

EE Board Exam April 1992 505. A coil has 6,000 turns of wire and a resistance of 380 ohms. The coil is rewound with the same quantity (weight) of wire, but has 13,400 turns. How many ohms will the new coil have? A. 1895 ohms B. 1825 ohms C. 1792 ohms D. 1905 ohms

Electron flow assumes charges flow from A. Negative to positive B. Negative to negative C. Positive to negative D. Positive to positive

For a carbon composition resistor, typical resistance values range from A. 2.7 Q to 22 MQ B. 1000 n to 10000 n C. 10 n to 10Mn D. 2.7 n to 2.7Gn

For a series AC circuit, is not used as a reference phasor. A. Voltage B. Impedance C. Current D. Conductance

For multi-plate capacitor, capacitance is proportional to A. Number of plates less one(n - 1) B. Number of plates plus one(n + 1) C. Number of plates less two(n - 2) D. Number of plates (n)

For parallel capacitors, total charge is A. The sum of individual charges B. Equal to the charge of either capacitors C. Equal to the product of the charges D. The quotient of the charges

In a multiple capacitor, the plate area is A. Increased B. The same C. Decreased D. Variable

In a pure capacitance, A. Current leads voltage by 90° B. Current leads voltage by 180° C. Current lags voltage by 90° D. Current lags voltage by 180° 97. The ohmic value of a resistor with

In a series circuit with unequal resistances the A. Highest R has the highest V B. Lowest R has the highest V C. Lowest R has the highest I D. Highest R has the highest I

In an RL series circuit, A. Current lags voltage by less than 90° B. Current lags voltage by 180° C. Current lags voltage by 90° D. Current leads voltage by 90°

In an inductive coil, the rate of rise of current is maximum A. Near the final maximum value of current B. At mid-value of current C. At half-power points D. After one time constant

In calculating maximum instantaneous power voltage or current is used. A. Peak B. Average C. Rms D. Instantaneous

In dividing or multiplying phasor quantities, form is used. A. Polar B. Rectangular C. Trigonometric D. Exponential

In the 5-band method of capacitor color coding, the first band indicates A. Temperature coefficient B. Tolerance C. 1st digit D. Capacitance value

It is impossible to change the voltage across a capacitor instantly, as this would produce current. A. Infinite B. Zero C. Low D. High

REE Board Exam April 2001 518. A round wire has 250 MCM. Find its diameter in inches. A. ½ B. ¼ C. 0.16 D. 0.08

REE Board Exam April 2001 524. The resistance of the field winding of a DC machine is 0.25 Ω at 25°C. When operating at full-load, the temperature of the winding is 75°C. The temperature coefficient of resistance of copper is 0.00427 per °C at 0°C. Find the resistance of the field winding at full-load. A. 0.298 Ω B. 0.315 Ω C. 0.512 Ω D. 0.271 Ω

REE Board Exam October 1998 522. Two copper conductors have equal length. The cross-sectional area of one conductor is three times that of the other. If the resistance of the conductor having smaller cross-sectional area is 20 Ω, what is the resistance of the other? A. 20/3 Ω B. 60 Ω C. 180 Ω D. 20/9 Ω

REE Board Exam October 2000 523. A copper bar has a length of 20 ft., width of 4 inches and thickness of 0.5 inch. If the resistivity of copper is 10.37 Ω-CM/ft, what is the resistance of the bar? A. 81.4 μΩ B. 8.14 μΩ C. 814 μΩ D. 0.814 μΩ

REE Board Exam October 2000 525. A coil of copper has resistance of 5.46 Ω at 75°C. What will be its resistance at 25°C? A. 4.58 Ω B. 4.84 Ω C. 5.02 Ω D. 4.35 Ω

The area of capacitor plates increases two times, then its capacitance A. Increases two times B. Increases four times C. Decreases two times D. Decreases four times

The capacitance of a capacitor is relativepermittivity. A. Directly proportional to B. Inversely proportional to C. Equal to D. Inversely proportional to the square of

The charging of a capacitor through a resistance obeys A. Exponential law B. Logarithmic law C. Linear law D. Square law

The electric field strength between capacitor plates has a unit of A. Volts per meter B. Volts per mil C. Amperes per meter D. Amperes per miL

The farad is not equivalent to which of the following combination of units B. C2 /J C. C/V D. J/V2

The hot resistance of an incandescent lamp is about times its cold resistance. 2 A. 10 B. 5 C. 50 D. 100

The of an alternating quantity is defined as the fractional part of a period or cycle through which the quantity has advanced from selected origin. A. Phase B. Frequency C. Amplitude D. Waveform

The potential gradient in a cable is maximum in A. Conductor B. Outer sheath C. Insulation D. Uniformly all over

The power factor of a certain circuit in which the voltage lags behind the current is 80 %. To increase the power to 100 %, it is necessary to add to the circuit. A. Inductance B. Capacitance C. Resistance D. Impedance

The ratio of the flux density to the electric field intensity in the dielectric is called A. Permittivity B. Field intensity C. Permeability D. Elasticity

The reciprocal of a complex number is A. A complex number B. A real number C. An imaginary number D. A whole number

The resistance of an insulator when its temperature is increased. A. Decreases B. Remains the same C. Increases D. Varies

What is the conductance of a circuit having three 10 n resistors in parallel? A. 0.3 S B. 3.33 S C. 0.33 S D. 30 S

What is the efficiency under the conditions of maximum power transfer? A. 50 % B. 100 % C. 25 % D. 75 %

When resistance are connected in parallel, the total resistance is A. Less than the smallest resistance in the connection B. Greater than the smallest resistance in the connection C. Between the smallest and greatest resistance in the connection D. Increasing and decreasing depending upon the supply voltage

When the net reactance in a series coil-capacitor circuit is zero at frequency f, the nature of its reactance of frequency 2f is A. Inductive B. Capacitive C. Resistive D. Infinite

When the temperature of copper wire is increased its resistance is A. Increased B. Decreased C. Constant D. Zero

When voltage is applied across a ceramic dielectric the electrostatic field produced is 50 times greater than air dielectric. The dielectric constant of ceramic therefore is A. 50 B. 100 C. 16.67 D. 5

Which is considered as the effect of a dielectric material? A. Increasing capacitance B. Decreasing capacitance C. Reducing the working voltage D. Increasing the distance between the plates

302. What is the value of a resistor with colors from left: Orange, Blue, Gold, and Silver? A. 34 ohms ± 10% B. 3.6 ohms ± 10% C. 3.4 ohms ± 10% D. 36 ohms ± 10%

304. Resistors with high value usually have lower wattage ratings because of _________. A. varying current B. lower current C. bigger size D. high current

305. Smaller resistors usually have ________ resistance value. A. small B. high C. low D. very small

343. Theorem used to simplify complex circuits wherein, the simplified circuit contains an equivalent open circuit resistance and open circuit voltage. A. Norton's B. Thevenin's C. Maxwell's D. Kirchhoff's

346. RN and IN of a Norton's equivalent circuit are known to be 100Ω and 10A, respectively. If a 400Ω load is connected, it will have a load current of A. 1 A B. 2 A C. 3 A D. 4 A

353. Nodal analysis is best used together with A. KVL B. KCL C. VDT D. CDT

357. The description of two sine waves that are in step with each other going through their maximum and minimum points at the same time and in the same direction A. phased sine wave B. sine waves in phase C. sine wave in coordination D. stepped sine waves

368. When comparing rms voltages and average voltages, which of the following statement is true, assuming sine waves? A. Either the rms voltage or the average voltage might be larger B. The rms voltage is always greater than the average voltage C. There will always be a very large difference between the rms voltage and the average voltage D. The average voltage is always greater than the rms voltage

375. If the current in an ac-circuit leads the voltage by 90°, the circuit is A. resistive B. capacitive C. inductive D. purely inductive

382. Ignoring any inductive effects, what is the impedance of RC series capacitor made up of a 56 kilo ohms resistor and a 0.33 μF capacitor at a signal frequency of 450 Hz? A. 66,730 ohms B. 57,019 ohms C. 45,270 ohms D. 10,730 ohms

392. A 6-Ω resistor is connected in series with a capacitive reactance of 8 Ω. If the supply voltage is 200 V, what is the circuit current magnitude? A. 14.28 A B. 20 A C. 25 A D. 33.33 A

394. The apparent power of a series RC network is given to be 4000 W. If R = 6 Ω, and XC = 8 Ω, calculate the true power of the network. A. 1200 W B. 2400 W C. 3200 W D. 4000 W

415. In a series ac-circuit, if the line frequency is more than the resonant frequency, the circuit behaves as A. resistive B. inductive C. reactive D. capacitive

416. If the line frequency of a parallel ac-circuit is less than the resonant frequency, the circuit behaves as A. resistive B. reactive C. capacitive D. purely inductive

426. The distance covered or traveled by a waveform during the time interval of one complete cycle. A. Frequency B. Wavelength C. Time slot D. Wave time

429. How many degrees are there in one complete cycle? A. 720 deg B. 360 deg C. 180 deg D. 90 deg

469. A 220 V, 60 Hz source is driving a series RL circuit. Determine the current in the circuit if R = 100 ohm XL = 100 ohm. A. 1.10 lagging B. 1.55 lagging C. 2.20 lagging D. 4.40 lagging

470. What is the resonant frequency of a circuit when an inductance of 1 uH and capacitance of 10 Picofarad are in series? A. 15.9 MHz B. 50.3 MHz C. 15.9 kHz D. 50.3 KHz

474. A coil of 15 H inductance and 10 ohms resistance is suddenly connected to a 20 volts DC source by closing the switch. The value of current 2 seconds after the switch is closed is A. 1.74 A B. 1.47 A C. 1.17 A D. 1.71 A

477. A relay has a resistance of 300 ohms and is switched to a 100 V DC supply. If the current reaches 63.2% of its final value at 0.02 sec, determine the inductance of the circuit. A. 5 H B. 6 H C. 4 H D. 13 H

478. Energy stored by a coil is doubled when its current is increased by ________ percent. A. 100 B. 141.4 C. 50 D. 25

479. A 60 volt potential difference is suddenly applied to a coil of inductive 60 mH and resistance 180 ohms. At what rate is it rising after 0.005 sec? A. 322 A/sec B. 223 A/sec C. 22.3 A/sec D. 32.2 A/sec

481. A capacitance of 10 microfarad is connected in series with a resistance of 8,000 ohms. If the combination is suddenly connected to a 100 V DC supply. Find the initial rate of rise in potential across the capacitor. A. 12500 V/s B. 125 V/s C. 1250 V/s D. 12.50 V/s

482. A 25 microfarad capacitor is connected in series with a 0.50 M-ohm resistor and a 120 volt storage battery. What is the potential difference in the capacitor 6 sec after the circuit is closed? A. 64 volts B. 46 volts C. 4.60 volts D. 6.40 volts

483. A capacitor of 2 microfarad with an initial charge q0 is connected across the terminals of a 10 ohm resistor and the switch is closed at t = 0. Find q0 (micro-coulomb) if the transient power in the resistor is known to be PR = 360e-10^(-5)t A. 1200 B. 120 C. 102 D. 2100

484. The transient current in a loss-free L-C circuit when excited from an ac source is _________ a/an sine wave . A. overdamped B. undamped C. underdamped D. critically damped

496. A two terminal black box contains a single element which can be R, L, C or M. As soon as the box is connected to a dc voltage source, a finite non-zero current is observed to flow through the element. The element is a/an A. resistance B. inductance C. capacitance D. Mutual inductance

499. A 1 µF capacitor charged through a 2 kΩ resistor by a 10 V dc source. The initial growth of capacitor voltage will be at the rate A. 316 V/ms. B. 5.0 V/ms C. 6.32 V/ms D. 10.0 V/ ms

602. How many circular mils does a round copper rod of 0.25 inch diameter have? A. 196,000 B. 62,500 C. 1,963,500 D. 49,000

603. A substance whose molecules consist of the same kind of atoms is called _________. A. mixture B. element C. compound D. none of these

607. The maximum number of electrons that can be accommodated in the last orbit is _________. A. 4 B. 8 C. 18 D. 2

619. The resistance of a material is ________ its area of cross-section. A. directly proportional to B. inversely proportional to C. independent of D. none of these

620. If the length and area of cross-section of a wire are doubled up, then its resistance __________. A. becomes four times B. remains unchanged C. becomes sixteen times D. none of these

634. Referring to Fig. 13.1, the value of the α50 will be ________. A. 0.005/°C B. 0.004/°C C. 0.1/°C D. 0.4/°C

637. Referring to Fig. 13.2, the value of α40 will be _________. A. 1/30 per °C B. 1/70 per °C C. 1/50 per °C D. 1/1200 per °C

651. REE Board Exam October 1998 The resistance of 120 meters of wire is 12 ohms. What is its conductance? A. 0.0521 siemens B. 0.0833 siemens C. 6 siemens D. 12 siemens

657. REE Board Exam October 1997 A 10-ohm and a 20-ohm resistance are connected in parallel. Another resistance of 5-ohm is connected in series with the two. If the supply voltage is 48 volts, what is the current through the 10-ohm resistor? A. 3.21 A B. 2.74 A C. 4.02 A D. 5.72 A

659. REE Board Exam September 2001 Three resistors 10-Ω, 15-Ω and 20-Ω are connected in series across a 48-V source. What is the voltage across the 15-Ω resistor? A. 20 V B. 16 V C. 24 V D. 12 V

660. REE Board Exam September 2001 Three resistors 10-Ω, 15-Ω and 20-Ω are connected in parallel. What is the total resistance? A. 3.56 Ω B. 4.62 Ω C. 0.217 Ω D. 45 Ω

668. ECE Board Exam November 1999 Which of the following is not a valid expression of ohm's law? A. E = IR B. R = PI C. R = E/I D. I = E/R

680. ECE Board Exam April 1998 An electronic device draws 300 watts from its 24 volt power source. Find effective resistance. A. 1.25 Ω B. 1.92 Ω C. 19.20 Ω D. 12.50 Ω

682. ECE Board Exam March 1996 What type of circuit whose parameters are constant which do not change with voltage or current? A. Tuned circuit B. Linear circuit C. Reactive circuit D. Lumped circuit

689. ECE Board Exam April 2001 If 3,300 ohms resistor and a 22,000 ohms resistor are connected in series, what is the total resistance? A. 18,700 ohms B. 25,300 ohms C. 5,500 ohms D. 2,870 ohms

693. ECE Board Exam April 1998 Find the current that flows through the filament of a 400 watt flat iron connected to a 220 volt power line. A. 50 mA B. 500 mA C. 5 mA D. 5 A

694. Four equal resistances are connected in parallel across a certain supply producing P power. How much power will be produced if the resistances are now connected in series across the same supply? A. 16P B. P/16 C. 4P D. P/4

707. The purpose of load in an electric circuit is to __________. A. increase the circuit current B. utilize electrical energy C. decrease the circuit current D. none of the above

708. Electrical appliances are not connected in series because __________ A. series circuit is complicated B. appliances have different current rating C. power loss is more D. none of the above

713. The circuit shown in Fig. 15.1 is called a series circuit because ________ electrical circuit figure 15.1 A. it contains a few resistances B. it carries the same current throughout the circuit C. it is a simple circuit D. none of the above

715. In Fig. 15.2 ____ electrical circuit figure 15.2 A. the lamp A will be brighter than lamp B B. the lamp B will be brighter than lamp A C. the two lamps will be equally bright D. none of the above

722. Two incandescent lamps of 100 W, 200 V are in parallel across 200 V supply. The total resistance will be _______. A. 800 ohms B. 200 ohms C. 400 ohms D. 600 ohms

729. The total conductance of the circuit shown in Fig. 15.7 is ________ electrical circuit figure 15.7 A. 13 mhos B. 1.6 mhos C. 6 mhos D. 2.5 mhos

739. Two equal resistances are connected in series across a certain supply. If the resistances are now connected in parallel across the same supply, the power produced will be ________ that of series connection. A. two times B. four times C. one-half D. one-fourth

744. If in Fig. 15.14, switches S1 and S2 are closed, then total circuit resistance is _______ electrical circuit figure 15.14 A. 400 ohms B. 1200 ohms C. 1000 ohms D. 2400 ohms

758. Which of the following statements is correct concerning the Fig. 16.6? electrical circuit figure 16.6 A. R2 and R3 form a series of path B. E is in series with R1 C. R1 is in parallel in R3 D. R1, R2 and R3 form a series of circuit

761. A 100 W, 110 V and 50 W, 110 V lamps are connected in series across a 220 V DC source. If the resistances of the two lamps are assumed to remain constant, the voltage across the 100 W lamp is _________ volt? A. 110 V B. 73.3 V C. 146.7 V D. 220 V

762. A potential divider of resistance of 50 ohms is connected across a 100 V DC source. A load resistance of 10 ohms is connected across a tap in the potential divider and the negative terminal of the source. If a current of 4 A flows towards the load, what is the current supplied by the source? A. 5.32 A B. 5.05 A C. 5.21 A D. 5.48 A

782. REE Board Exam October 2000 An electric heater is used to heat up 600 grams of water. It takes 14 minutes to raise the temperature of water by 40°C. If the supply voltage is 220 volts,what is the power rating of the heater neglecting heat losses? A. 180 W B. 120 W C. 200 W D. 60 W

783. REE Board Exam April 2001 A 100 liter of water is heated from 20°C to 40°C. How many kWHR of electricity is needed assuming no heat loss? A. 4.2 B. 2.3 C. 5.6 D. 3.7

785. ECE Board Exam November 1995 Two heaters A and B are in parallel across supply voltage V. Heater A produces 500 kcal in 20 minutes and B produces 1000 kcal in 10 minutes. The resistance of A is 10 ohms. What is the resistance of B, if the same heaters are connected in series voltage V? A. 4.5 ohms B. 2.5 ohms C. 4.5 ohms D. 0.14 ohm

786. In the SI system of units, the unit of force is A. kg-wt B. Newton C. Joule D. N-m

796. Two heaters, rated at 1000 W, 250 volts each, are connected in series across a 250 volt, 50 Hz A.C. mains. The total power drawn from the supply would be __________ watt. A. 1000 B. 500 C. 250 D. 2000

800. For a given line voltage, four heating coils will produce maximum heat when connected A. all in parallel B. all in series C. with two parallel pairs in series D. one pair in parallel with the other two in series

801. Four heaters having the same voltage rating will produce maximum heat if connected in A. Series B. Parallel C. Series-Parallel D. Parallel-Series

823. ECE Board Exam April 1999 What is a node? A. A terminal point for a loop current B. A connection point between two or more conductors C. A formula D. A mathematical fiction

826. ECE Board Exam November 1996 Find the Thevenin's impedance equivalent across R2 of a linear close circuit having 10 volt supply in series with two resistors (R1=50 ohms and R2 = 200 ohms). A. 400 ohms B. 40 ohms C. 4 ohms D. 4 kohms

834. An passive element in a circuit is one which __________. A. supplies energy B. receives energy C. both receives and supplies energy D. none of these

838. In the circuit shown in Fig. 17.6, there are _________ junctions. electrical circuit figure 17.6 A. three B. four C. two D. none of these

850. Fig. 3.4(b) shows the Thevenin's equivalent circuit of Fig. 17.9(a). The value of Thevenin's voltage Vth is ________. electrical circuit figure 17.9 A. 20 V B. 24 V C. 12 V D. 36 V

854. Fig. 18.2(b) shows Norton's equivalent circuit of Fig. 3.5(a). The value of RN is _______. electrical circuit figure 18.2 A. 5 Ω B. 4.5 Ω C. 10.5 Ω D. none of the above

857. Norton's theorem is ________ Thevenin's theorem. A. A the same as. B. converse of C. equal to D. none of the above

859. Norton's theorem is __________ form of an equivalent circuit A. voltage B. current C. both voltage and current D. none of the above

863. If in Fig. 18.3(a), the value of IN is 3 A, then value of Vth in Fig. 18.3(b) will be _________. electrical circuit figure 18.3 A. 1 V B. 9 V C. 5 V D. none of these

869. For the circuit shown in Fig. 18.4, the power transferred will be maximum when RL is equal to _______. electrical circuit figure 18.4 A. 4.5 Ω B. 6 Ω C. 3 Ω D. none of these

879. Maxwell's loop current method of solving electrical networks A. uses branch currents B. utilizes Kirchhoff's voltage law C. is confined to single-loop circuits D. is a network reduction method

884. While Thevenizing a circuit between two terminals, Vth equals A. short-circuit terminal voltage B. open circuit terminal voltage C. EMF of the battery nearest to the terminal D. net voltage available in the circuit

896. A 12 volt source with an internal resistance of 1.2 ohms is connected across a wire-wound resistor. Maximum power will be dissipated in the resistor when its resistance is equal to A. zero B. 1.2 ohm C. 12 ohms D. infinity

897. Three 3.33 Ω resistors are connected in wye. What is the value of the equivalent resistors connected in delta? A. 3.33 Ω B. 10 Ω C. 6.67 Ω D. 20 Ω

900. Find the power dissipation in the 6 ohms resistor in the next figure. electrical circuit figure 18.9 A. 54 W B. 216 W C. 121.5 W D. 150 W

An open resistor when checked with an ohmmeter reads A. Zero B. Infinite C. High but within the tolerance D. Low but not zero

ECE Board Exam April 1998 534. Determine the equivalent work of 166 watt-second. A. 10 joules B. 100 joules C. 16.6 joules D. 166 joules

ECE Board Exam April 1999 587. If an electronic resistor does not have the fourth color strip it means it has a tolerance of _________. A. 5% B. 20% C. 10% D. 1%

ECE Board Exam April 2001 552. Represents the current flow produced by one volt working across one ohm of resistance. A. resistance B. ampere C. voltage D. electromotive force

ECE Board Exam April 2001 565. What is the resistance of an open fuse circuit? A. at least 1000 ohms B. infinity C. zero D. 100 ohms at standard temperature

ECE Board Exam November 1995 532. What composes all matter whether a liquid, solid or gas? A. electrons B. atoms C. protons D. neutrons

ECE Board Exam November 1997 559. An insulating element or material has capability of _________. A. storing voltage B. preventing short circuit between two conducting wires C. conducting large current D. storing high current

ECE Board Exam November 1997 585. What does the second strip of an electronic resistor color code represent? A. Tolerance B. Second digit of the value C. Temperature D. Multiplier

ECE Board Exam November 1997 591. Term used in electronic measuring device when a metal increases resistance due to heat produced by current flowing through them. A. positive resistance coefficient B. positive temperature coefficient C. negative temperature coefficient D. negative resistance coefficient

ECE Board Exam November 1999 555. What will happen to an atom if an electron is either taken out or taken into the same atom? A. becomes a negative ion B. becomes an ion C. becomes a positive ion D. nothing will happen

ECE Board Exam November 2001 544. What do you call the element that conducts electricity very readily? A. semi-conductors B. conductors C. insulators D. dielectric

ECE Board Exam November 2001 546. A chemical combination of elements can be separated by chemical means but not by physical means. It is created by chemically combining two or more elements. A. molecules B. compound C. matter D. mixture

ECE Board Exam November 2001 548. Calculate the equivalent power in watt of 100 joules per second. A. 1.66 watts B. 100 watts C. 16.66 watts D. 1,000 watts

ECE Board Exam November 2001 563. Find the value of a resistor with the following color codes: Orange, Yellow, Red, Red A. 34 k ohms +/-5% B. 3.4 ohms +/-2% C. 3.4 k ohms +/-10% D. 34 k ohms +/-20%

If the capacitance of mica capacitor is 5 times the capacitance of air capacitor, then the relative permittivity of mica is A. 2.5 B. 5 C. 10 D. 25

In Norton's theorem, the short circuit current is obtained by A. Opening the load terminals B. Shorting the load terminals C. Opening the voltage source D. Shorting the voltage source

Metal tin becomes superconductor at approximately A. 6 K B. 3.7 K C. 5 K D. 4.7 K

The ratio of maximum value to the effective value of an alternating quantity is called A. Form factor B. Peak factor C. Dynamic factor D. Leakage factor

Under the conditions of maximum power transfer, a voltage source is delivering a power of 15 W to the load. What is the power generated by the source? A. 60 W B. 30 W C. 15 W D. 4 W

237. If a battery of 6 V is applied across terminals 1 and 2 in Fig. 15.11, then current in the horizontal 2 ohm resistor will be ________ electrical circuit figure 15.11 A. 1 A B. 2 A C. 3 A D. 0.5 A

308. If you need a 1.25 kΩ resistance and you only have resistors of 5 kΩ, how many of these available resistors you should connect in parallel to get a 1.25 kΩ value? A. 2 B. 3 C. 4 D. 5

309. Insulating elements or materials has a capability of A. allowing electric current to flow B. supporting charge flow C. preventing short circuit between conducting wires D. making electrical circuits to be completed

310. _________ is used to store electrical energy in an electrostatic field? A. A transformer B. A battery C. A capacitor D. An inductor

311. What factors determine the capacitance of a capacitor? A. Area of the plates, amount of charge on the plates and the dielectric constant of the material between the plates B. Area of the plates, voltage on the plates and the distance between the plates C. Area of the plates, distance between the plates, and the dielectric constant of the material between the plates D. Area of the plates, voltage on the plates and dielectric constant of the material between the plates

315. A parallel plate capacitor has the following values: k = 81; d = 0.025 inches; A = 6 square inches. What is the capacitance of the capacitor? A. 4.372 picofarad B. 43.72 picofarad C. 4372 picofarad D. 437.2 picofarad

318. A 20 μF capacitor is charged by a 12-V battery. What is the stored energy at the capacitor? A. 2.88 x 10^-3 J B. 1.07 x 10^-3 J C. 1.44 x 10^-3 J D. 2.88 x 10^-2 J

338. How many nodes are needed to completely analyze a circuit according to Kirchhoff's current law? A. two B. all nodes in the circuit C. one less than the total number of nodes in the circuit D. one

351. The return point in a circuit, where all voltage measurements are referred. A. node B. junction C. ground D. loop

412. Find the half-power bandwidth of a parallel resonant circuit, which has a resonant frequency of 3.6 MHz and a Q of 218. A. 606 kHz B. 58.7 kHz C. 16.5 kHz D. 47.3 kHz

422. Term used for the out of phase, non-productive power associated with inductors and capacitors. A. Effective power B. True power C. Reactive power D. Peak envelope power

425. The product of current and voltage in an AC circuit refers to the A. Real power B. Useful power C. Apparent power D. DC power

449. An alternating current given by i = 10 sin 314 t. The time taken to generate two cycles of current is A. 20 ms B. 10 ms C. 40 ms D. 50 ms

450. In a pure resistive circuit, the instantaneous voltage and are current are given by: v = 250sin314t i = 10sin314t The peak power in the circuit is A.1250 W B. 25 W C. 2500 W D. 250 w

451. Find the half power bandwidth of a parallel resonant circuit which has a resonant frequency of 3.6 MHz and Q of 218. A. 606 kHz B. 58.7 kHz C. 16.5 kHz D. 47.3 kHz

476. A 200 volt DC supply is suddenly switched to a relay coil which has a time constant of 3 ms. If the current in the coil reaches 0.20 ampere after 3 ms determine the steady state value of the current. A. 0.361 A B. 0.163 A C. 0.316 A D. 0.631 A

480. A voltage rise linearly form zero to 100 volts in 1 second, falls instantaneously to zero at t = 1 second and remains zero thereafter. This voltage is applied to an RL series circuit in which R = 5 ohms and L = 100 mH. What is the current when t = 0.50 second? A. 6.90 A B. 96 A C. 9.60 A D. 69 A

485. A series RLC circuit with R = 5 ohms, L = 0.10 H, C= 500 microfarad has a constant voltage V = 10 volts applied at t = 0. Find the resulting transient current. A. 0.707e-50t sin 139t B. 0.272e-25t sin 278t C. 0.720e-25t sin 139t D. none of these

488. A series RLC circuit with R = 1 kΩ, L = 1 H and C = 6.25 μF is suddenly connected across a 24 V dc source. At t = 0, i= 0 and q = 0. Determine the current after 0.01 sec. A. 3.45 mA B. 4.61 mA C. 5.40 mA D. 5.05 mA

491. A DC voltage source is connected across a series RLC circuit, under steady state conditions, the applied DC voltage drops entirely across the A. R only B. L only C. C only D. R & L combinations

495. Transient current in a circuit results from A. voltage applied to the circuit B. impedance of the circuit C. changes in the stored energy in inductors and capacitors D. resistance of the circuit

606. The mass of a proton is ___________ the mass of an electron. A. equal to B. less than C. about 1837 times D. 200 times

608. The electrons in the last orbit of an atom are called _________ electrons. A. free B. bound C. valence D. thermionic

621. A length of wire has a resistance of 6 ohms. The resistance of a wire of the same material three times as long and twice the cross-sectional area will be ________. A. 36 ohms B. 12 ohms C. 9 ohms D. 1 ohm

632. Eureka has _________ temperature coefficient of resistance. A. positive B. negative C. almost zero D. none of these

638. The value of α0 of a conductor is 1/236 per °C. The value of α18 will be _________. A. 1/218 per °C B. 1/272 per °C C. 1/254 per °C D. none of these

640. A good electric conductor is one that A. has low conductance B. is always made of copper wire C. produces a minimum voltage drop D. has few free electrons

645. A cylindrical wire 1 m in length, has a resistance of 100. What would be the resistance of a wire made from the same material both the length and the cross-sectional area are doubled? A. 200 B. 400 C. 100 D. 50

647. A unique feature of a wire-wound resistor is its A. lower power rating B. low cost C. high stability D. small size

658. REE Board Exam March 1998 Two resistances of 10 and 15 ohms, each respectively are connected in parallel. The two are then connected in series with a 5-ohm resistance. It is then connected across a 12-V battery, what are the current and power? A. 1.2 A, 17.28 W B. 0.96 A, 11.52 W C. 1.09 A, 13.1 W D. 1.5 A, 20.25 W

665. REE Board Exam October 2000 Two 10-ohm parallel resistors are connected in series with a 5-ohm resistor. The combination is then connected across a 24 volts battery. Find the voltage drop across the 5-ohm resistor. A. 6 V B. 18 V C. 12 V D. 20 V

669. ECE Board Exam November 2000 A simple electronic equipment which takes a 2 amperes current from a power source has a total load resistance of 100 ohms. How much power does it use? A. 200 watts B. 100 watts C. 400 watts D. 50 watts

670. ECE Board Exam November 1996 What do you expect when you use the two 20 kohms, 1 watt resistor in parallel instead of one 10 kohms, 1 watt? A. Provide lighter current B. Provide wider tolerance C. Provide more power D. Provide less power

702. Ohm's law is not applicable to A. copper B. silver C. silicon carbide D. aluminum

703. The practical unit of electrical energy is A. watt B. kilowatt C. kilowatt-hour D. megawatt

704. A 100 watt lamp working for 20 hours will consume ________ units. A. 200 B. 20 C. 2 D. 5

732. The current in 10 ohms resistor in Fig. 15.8 is ________ electrical circuit figure 15.8 A. 3 A B. 2.5 A C. 1.5 A D. 3.5 A

736. The resistance between terminals 1 and 2 in Fig. 15.11 is ________ electrical circuit figure 15.11 A. 2 ohms B. 1.5 ohms C. 1 ohm D. 4 ohms

741. Referring to Fig. 15.13, the resistance across terminals AF is ________ electrical circuit figure 15.13 A. 20.5 ohms B. 18 ohms C. 11 ohms D. none of the above

742. Referring to Fig. 15.13, the current in 18 ohms resistor will be ________ electrical circuit figure 15.13 A. 2 A B. 1.5 A C. 1 A D. none of the above

753. In the parallel circuit of Fig.16.1, the value of V0 is ________ volt. electrical circuit figure 16.1 A. 12 B. 24 C. 0 D. -12

755. In Fig 16.3, there is a drop of 20 V on each resistor. The potential of point A would be _________ volt. electrical circuit figure 16.3 A. +80 B. -40 C. +40 D. -80

769. REE October 1998 How many calories does an electric heater of 100 watts generate per second? A. 10 B. 1000 C. 23.88 D. 42.25

772. EE Board Exam October 1990 In an electric heater the inlet temperature is 15°C. Water is flowing at the rate of 300 grams per minute. The voltmeter measuring voltage across the heating element reads 120 volts and an ammeter measuring current taken reads 10 amperes. When steady state is finally reached, what is the final reading of the outlet thermometer? A. 57.6°C B. 68.4°C C. 72.6°C D. 42.6°C

773. EE Board Exam October 1991 Four cubic meters of water is to be heated by means of four 1.5 kW, 230-V immersion heating elements. Assuming the efficiency of the heater as 90%, determine the time required in boiling the water if the initial temperature is 20°C and if all four elements are connected in parallel. A. 71 hrs B. 63 hrs C. 69 hrs D. 66 hrs

779. REE Board Exam October 1999 The quantity of heat required to raise the temperature of water by 1°C. A. energy B. specific heat C. calorie D. BTU

784. REE Board Exam April 2002 Ten (10) kW is equal to __________ gram-cal/sec. A. 156 B. 436 C. 2,388 D. 425

787. The basic unit of electric charge is A. ampere-hour B. watt-hour C. coulomb D. farad

789. Two heating elements, each of 230-V, 3.5 kW rating are first joined in parallel and then in series to heat same amount of water through the same range of temperature. The ratio of the time taken in the two cases would be A. 1:2 B. 2:1 C. 1:4 D. 4:1

790. If a 220 V heater is used on 110 V supply, heat produced by it will be _________ as much A. one-half B. twice C. one-fourth D. four times

792. The electric energy required to raise the temperature of a given amount of water is 1000 kWh. If heat losses are 25%, the total heating energy required is ____________ kWh. A. 1500 B. 1250 C. 1333 D. 1000

804. REE Board Exam April 1997 A circuit consisting of three resistors rated: 10 ohms, 15 ohms and 20 ohms are connected in delta. What would be the resistance of the equivalent wye connected load? A. 0.30, 0.23 & 0.15 ohm B. 3.0, 4.0 & 5.0 ohms C. 3.33, 4.44 & 6.66 ohms D. 5.77, 8.66 & 11.55 ohms

805. EE Board Exam October 1994 The equivalent wye element of a 3 equal resistors each equal to R and connected in delta is A. R B. 3R/2 C. R/3 D. 3R

817. EE Board Exam August 1977 In the figure below R1 = 1 ohm, R2 = 1 ohm, R3 = 3 ohms, I2 = 2 A and VB = 120 V. Find Eg. electrical circuit figure 17.3 A. 182.41 V B. 153.32 V C. 164.67 V D. 157.22 V

818. EE Board Exam October 1980, April 1984 In the dc circuit as shown, the high resistance voltmeter gives a reading of 0.435 volt. What is the value of the resistance R? electrical circuit figure 17.4 A. 4 ohms B. 5 ohms C. 3 ohms D. 2 ohms

832. A 2-wire dc distribution line has sending end voltage of 240 V and total line resistance of 0.4 ohm. The maximum kW that can be transmitted by the line is ________. A. 108 B. 72 C. 36 D. 144

835. An electric circuit contains __________. A. active elements only B. passive element only C. both active and passive elements D. none of these

836. A linear circuit is one whose parameters (e.g. resistances etc.) ___________. A. change with change in current B. change with change in voltage C. do not change with change in voltage and current D. none of these

840. The circuit shown in Fig. 17.6 has __________ loops. electrical circuit figure 17.6 A. two B. four C. three D. none of the above

842. To solve the circuit shown in Fig. 17.7 by Kirchhoff's laws, we require ________ electrical circuit figure 17.7 A. one equation B. two equations C. three equations D. four equations

845. To solve the circuit shown in Fig. 17.7 by Maxwell's mesh current equation, we require electrical circuit figure 17.7 A. one equation B. three equations C. two equations D. none of these

852. The open-circuited voltage at terminals AB in Fig. 17.9(a) is electrical circuit figure 17.9 A. 12 V B. 20 V C. 24 V D. 40 V

853. For transfer of maximum power in the circuit shown in Fig. 17.9(a), the value of RL should be _________. electrical circuit figure 17.9 A. 3.5 Ω B. 6.4 Ω C. 7.4 Ω D. 15 Ω

858. In the analysis of a vacuum tube circuit, we generally use _________. A. superposition B. Norton's C. Thevenin's D. reciprocity

865. Under the conditions of maximum power transfer, the efficiency is _________. A. 75% B. 100% C. 50% D. 25%

868. Under the conditions of maximum power transfer, a voltage source is delivering a power of 30 W to the load. The power generated by the source is __________. A. 45 W B. 30 W C. 60 W D. 90 W

874. Delta/star of star/delta transformation technique is applied to _________. A. one terminal B. two terminal C. three terminal D. none of the above

875. Kirchhoff's current law is applicable to only A. closed loops in a network B. electronic circuits C. conjunctions in a network D. electric circuits

878. The algebraic sign of an IR drop is primarily dependent upon the A. amount of current flowing through it B. value of R C. direction of current flow D. battery connection

882. Superposition theorem is can be applied only to circuits having _________ elements. A. non-linear B. passive C. linear bilateral D. resistive

883. The Superposition theorem is essentially based on the concept of A. duality B. linearity C. reciprocity D. non-linearity

A linear circuit is one whose parameters A. Change with change in voltage B. Change with change in current C. Do not change with voltage and current D. Change with change in voltage and current

A trimmer is a variable capacitor in which capacitance is varied by changing the A. Number of plates B. Dielectric C. Distance between plates D. Plate area

An electric circuit contains A. Passive elements B. Active elements C. Both active and passive elements D. Reactive elements

Delta to wye or wye to delta transformation technique is applied to a network. A. One-terminal B. Two-terminal C. Three-terminal D. Complex

ECE BOARD NOV 2001 527. ________ is anything that has weight had occupies space. It may be solid, liquid or gas. A. Amalgam B. Alloy C. Matter D. Compound

ECE Board Exam April 1998 566. When should a fuse be replaced with a higher rated unit? A. when the fuse of the original value is small in size B. when the original is not available C. never D. if it blows

ECE Board Exam April 1999 556. The energy in an electron that is called the energy of motion A. electromotive force B. kinematics C. kinetic energy D. potential energy

ECE Board Exam April 2001 561. A three-terminal resistor with one or more sliding contacts which functions as an adjustable voltage divider A. Rheostat B. Bleeder resistor C. Potentiometer D. Voltage divider

ECE Board Exam March 1996 590. Which of the following statement is incorrect? A. open transistor has three (3) terminals B. transistors have three (3) terminals C. typical power rating of carbon-composition resistor ranged 0.001 W to 0.1 W D. potentiometer has three (3) terminals

ECE Board Exam November 1995 579. Which of the following statement is correct? A. Potentiometer has two terminals B. Transistor has two terminals C. Typical power rating of a carbon-composition resistor ranged from 0.125 W to 2 W D. Open resistor has small resistance

ECE Board Exam November 1996 577. The area of a conductor whose diameter is 0.001 inch is equal to A. One micron B. One angstrom C. One circular mil D. One steradian

ECE Board Exam November 1997 543. One of the following characteristics of a resistive material which do not change its resistive value with respect to time is its ___________. A. fidelity B. sensitivity C. stability D. selectivity

ECE Board Exam November 2000 574. Find the lowest resistance value of the following resistors. A. White, black, black B. Violet, gray, yellow, silver C. Red, black, gold D. Gray, gray, black

ECE Board Exam November 2001 533. What is a physical combination of compounds or elements NOT chemically combined that can be separated by physical means? A. substance B. atom C. mixture D. molecule

ECE Board Exam November 2001 538. The motion of charged particles especially colloidal particles through a relative stationary liquid under the influence of an applied electric provided. A. hysteresis B. electrolysis C. electrophoresis D. electro analysis

EE Board Exam April 1992 506. A copper wire of unknown length has a resistance of 0.80 ohm. By successive passes through drawing dies, the length of the wire is increased by 2 ½ times its original value. Assuming that resistivity remains unchanged during the drawing process, determine the new value of its resistance. A. 4 ohms B. 3 ohms C. 5 ohms D. 6 ohms

EE Board Exam April 1993 508. A kilometer of wire having a diameter of 11.7 mm and a resistance of 0.031 ohm is drawn down so that its diameter is 5.0 mm. What does its resistance become? A. 0.85 ohm B. 0.78 ohm C. 0.93 ohm D. 0.81 ohm

For maximum power transfer, what is the relation between load resistance RL and internal resistance R of the voltage source? A. RL = 2 r B. RL = 1.5 r C. RL = r D. RL = 3 r

High resistance values are a consequence of the of the film. A. Thickness B. Length C. Thinness D. Area

REE Board Exam October 1998, September 2001 511. The resistance of a copper wire at 30°C is 50 ohms. If the temperature coefficient of copper at 0°C is 0.00427, what is the resistance at 100°C? A. 72.26 ohms B. 54.25 ohms C. 63.24 ohms D. 58.15 ohms

The wavelength of an alternating waveform depends upon the of the variation. A. Period B. Number C. Frequency D. Amplitude

.The factor 0.707 for converting peak to rms applies only to A. Square waves B. Triangle waves C. Sawtooth waves D. Sine waves

330. Two resistors, R1 = 100 Ω and R2 = 200 Ω are connected in parallel. If the current through R1 is 1 A, what would be the current on R2? A. 0.125 A B. 0.25 A C. 0.35 A D. 0.50 A

337. The power in a circuit consisting of two equal resistors in series is known to be 10 watts. If the two resistors are connected in parallel, what would be the circuit power dissipation? A. 2.5 watts B. 5 watts C. 20 watts D. 40 watts

354. Three 100 Ω resistors are connected in a tee-form (T) network and is set up between a 100 V supply and a load resistor RL. If maximum power transfer is desired, what should be the resistance of the load resistor RL? A. 50 Ω B. 75 Ω C. 125 Ω D. 150 Ω

363. The time taken by an alternating voltage, v = 100sin240πt to reach 50V for the first time A. 358 μs B. 695 μs C. 358 ms D. 695 ms

372. The power dissipated across the resistance in an AC circuit A. real power B. reactive power C. apparent power D. true power

373. In AC circuit, resistors will dissipate what power? A. reactive B. passive C. inductive D. true

377. If the current and voltage in an ac-circuit has a phase difference, it would mean the load is A. resistive B. capacitive C. inductive D. reactive

387. What is the power factor (pf) of a series RL circuit having R = 50Ω and XL = 20Ω? A. 0.63 B. 0.71 C. 0.81 D. 0.93

398. What is the significance of connecting loads in parallel? A. it makes power consumption less B. it provides greater efficiency C. it increases the safety factor D. it allows independent operations of loads

410. Characteristics of the current in a series R-L-C circuit at resonance. A. It is dc B. It is a minimum C. It is zero D. It is at maximum

419. A parallel LC network with L = 100 mH and C = 25 μF will resonate at what frequency? A. 25 Hz B. 45.5 Hz C. 75.6 Hz D. 100 Hz

424. A 240 V, 25 Hz sinusoidal generator is connected to a 20 ohms resistor. Determine the instantaneous current when elapsed time is 0.01 second. A. 15043A B. 16.30 A C. 16.97 A D. 12.00 A

427. The power dissipated across the resistance in an AC circuit. A. Real power B. Reactive power C. Apparent power D. True power

436. What do you mean by root-mean-square (rms) value? A. It is the average value B. It is the effective value C. It is the value that causes the same heating effect as the DC voltage D. b or c

437. The maximum instances value of a varying current, voltage or power equal to 1.414 times the effective value of a sine wave. A. RMS value B. Peak value C. Effective value D. Peak to Peak value

473. The rate of rise of current through an inductive coil is maximum A. after 1 time constant B. at the start of current flow C. near the final maximum value of current D. at 63.2% of its maximum steady state value

597. The copper field coils of a motor was measured at 21°C and found to have a resistance of 68 Ω. After the motor has run for a given time, the resistance is found to be 96 Ω. What is the hot temperature of the winding? A. 106.36°C B. 166.30°C C. 103.66°C D. none of these

598. A wire has a resistance of 30 Ω at 20°C. What will its resistance be at 60°C? Assume the temperature coefficient of resistance to be 0.000385 at 20°C. A. 34.26 Ω B. 36.42 Ω C. 32.46 Ω D. none of these

624. The SI unit of conductivity is ________. A. ohm-m B. ohm/m C. mho-m D. mho/m

629. The value of α (i.e. temperature coefficient of resistance) depends upon A. length of the material B. cross-sectional area of the material C. volume of the material D. nature of the material and temperature

642. A coil has a resistance of 100 Ω at 90°C. At 100°C, its resistance is 101 Ω. The temperature coefficient of wire at 90°C is A. 0.01 B. 0.1 C. 0.0001 D. 0.001

676. ECE Board Exam November 1997 How much is the equivalent power in watts can a 3 horse power provide? A. 3000 watts B. 248.66 watts C. 1492 watts D. 2238 watts

677. ECE Board Exam March 1996 The current needed to operate a soldering iron which has a rating of 600 watts at 110 volts is A. 18,200 A B. 0.182 A C. 66,000 A D. 5.455 A

678. ECE Board Exam November 1997 Find the power across the resistor of 5 ohms delivered from a battery of an internal resistance of 3 ohms and a constant emf of 4 volts. A. 120 watts B. 100 watts C. 60 watts D. 1.25 watts

683. ECE Board Exam April 2000 If three circuits, each with a value of 560 ohms are connected in parallel, what is the total resistance of the combination? A. 1680 ohms B. 560 ohms C. 18567 ohms D. 187 0hms

685. ECE Board Exam April 1999 Find used power of a circuit whose power source supplies 20 volts and a load resistance of 200 ohms. A. 1 watt B. 4 kilowatts C. 10 watts D. 2 watts

725. The resistance across terminals AC in Fig. 15.5 is ________ electrical circuit figure 15.5 A. 36 ohms B. 9 ohms C. 18 ohms D. 8 ohms

727. If a battery of 24 V is applied across terminals AB of the circuit shown in Fig. 15.6, then current in 2 ohm resistor will be ________ electrical circuit figure 15.6 A. 3 A B. 6 A C. 2.5 A D. 1.5 A

730. If 10 ohms resistance is removed in Fig. 15.7, then total conductance of the circuit will be ________ electrical circuit figure 15.7 A. 3 mhos B. 6 mhos C. 2 mhos D. 1.5 mhos

747. If in Fig. 15.14 switches S1 and S2 are open, then lamp L1 will give output _______ electrical circuit figure 15.14 A. less than 40 W B. more than 40 W C. equal to 40 W D. none of the above

756. From the voltmeter reading of Fig. 16.4, is it obvious that electrical circuit figure 16.4 A. the 3 Ω resistor is short circuited B. the 6 Ω resistor is short circuited C. nothing is wrong with the circuit D. the 3 Ω resistor is open-circuited

759. What is the equivalent resistance in ohms between points A and B of Fig. 16.7? All resistances are in ohms electrical circuit figure 16.7 A. 12 B. 14.4 C. 22 D. 2

760. What do you call a resistor that does not obey Ohm's Law? A. Potentiometer B. Carbon-Film Resistor C. Wire-Wound Type D. Non-linear Resistor

767. REE Board Exam October 1997 A process equipment contains 100 gallons of water at 25°C. It is required to bring it to boiling in 10 minutes. The heat loss is estimated to be 5%. What is the kW rating of the heater? A. 125 kW B. 252 kW C. 50.5 kW D. 207 kW

770. REE Board Exam October 1997 The electric energy required to raise the temperature of water in a pool is 1000 kWh. If the heat losses are 25%, the heating energy required will be ___________. A. 1111 kWh B. 1266 kWh C. 1750 kWh D. 1333 kWh

825. ECE Board Exam April 1998 How many nodes are needed to completely analyze a circuit according to Kirchhoff's current law? A. One B. Two C. One less than the total number of nodes in the circuit D. All nodes in the circuit

827. ECE Board Exam November 1995 In order to match the load to the generator means making load resistance __________. A. lower than generator's internal resistance B. increased to more generator's internal resistance C. decreased D. equal to generator's internal resistance

847. The current in 2 Ω horizontal resistor in Fig. 17.8 is _________. electrical circuit figure 17.8 A. 10 A B. 5 A C. 2 A D. 2.5 A

861. Fig. 18.3(a) shows Norton's equivalent circuit of a network whereas Fig. 18.3(b) shows its Thevenin's equivalent circuit. The value of Vth is ________. electrical circuit figure 18.3 A. 1.5 V B. 0.866 V C. 3 V D. 6 V

Another term for superconductor. A. Generic conductor B. Ultraconductor C. Cryotron D. Cryogenic conductor

ECE Board Exam April 2000 540. Determine which of the following has the least number of electrons found at the outer shell. A. semi-insulator B. insulator C. semiconductor D. conductor

ECE Board Exam April 2001 545. Which of the following material is referred to as a medium whereby electrons can move easily from atom to atom? A. insulator B. dielectric C. mica D. conductor

ECE Board Exam April 2001 549. It is a neutral particle that has no electrical charge. A. atom B. proton C. electron D. neutron

ECE Board Exam November 1995 553. When an atom gains an additional _________, it results to a negative ion. A. atom B. neutron C. proton D. electron

ECE Board Exam November 1996 580. _______ is one factor that does not affect resistance. A. Resistivity B. Cross sectional area C. Length D. Mass

ECE Board Exam November 1997 582. Find the value of resistor with the following color codes; Brown, White, Orange, Red A. 190 ohms 10% B. 19 k ohms 2% C. 1.9 k ohms 10% D. 19 k ohms 20%

ECE Board Exam November 1998 575. If the bands on a resistor are yellow, violet, red and gold, what is the resistance value? A. 470 ohms 5% B. 470 ohms 10% C. 47000 ohms 5% D. 4700 ohms 5%

The ratio between the reactive power and the apparent power of an ac load is called A. Quality factor B. Power factor C. Power ratio D. Reactive power

The reason why alternating current can induce voltage is A. It has high peak value B. It has a stronger magnetic field than direct current C. It has a constant magnetic field D. It has a varying magnetic field

Which of the following does not generally affect the value of a capacitor? A. The dielectric material used B. The surface area of the plates C. The thickness of the dielectric D. The voltage applied to the plate

Why are inductance and capacitance not relevant in a dc circuit? A. Because it is a simple circuit B. Because dc circuits require only resistance as load C. Because they do not exist in a dc circuit D. Because frequency of dc is zero

421. The description of two sine waves that are in step with each other going through their maximum and minimum points ate the same time and in the same direction. A. Sine waves in phase B. Stepped sine waves C. Phased sine waves D. Sine waves in coordination

430. The impedance in the study of electronics is represented by resistance and _________ . A. Reactance B. Inductance and capacitance C. Inductance D. capacitance

433. The relationship of the voltage across an inductor to its current is described as A. Leading the current by 90 deg B. Lagging the current by 90 deg C. Leading the current by 180 deg D. In phase with the current

438. If an AC signal has a peak voltage of 55 V, what is the average value? A. 35 V B. 61.05V C. 86.34 V D. 38.89 V

440. A 220-V, 60Hz is driving a series RL circuit. Determine the current if R = 100 ohms and 20 mH inductance A. 2.2 A (lagging) B. 2.0 A (lagging) C. 2.2 A (leading) D. 2.0 A (leading)

442.What is the time constant of a 500 mH coil and a 3300 ohm resistor in series? A. 0.00015 sec B. 6.6 sec C. 0.0015 sec D. 0.0000015 sec

444. The reactance of a 25 mH coil at 5000 Hz which of the following? A. 785 ohms B. 785000 ohms C. 13 ohms D. 0.0012 ohms

452. A current of 10 A and a pf of 0.8 lagging is taken from a single phase 250 V supply. The reactive power of the system is_______. A. 1500 B. 2000 C. 250 D. not

494. An inductor L carries steady state current I0, suddenly at time t = 0 the inductor is removed from circuit and connected to a resistor R. The current through the inductor at time t is equal A. I0e-Rt/L B. I0 (1-e-Rt/L) C. I0e+Rt/L D. I0 (1-e+Rt/L)

5. For a parallel AC circuit, is used as a reference phasor. A. Voltage B. Power C. Current D. Resistance

573. Determine the equivalent horse power of 2.611 kilowatts. A. 3.50 hp B. 2.50 hp C. 2.25 hp D. 1.50 hp

592. A 1 km cable consists of 12 identical strands of aluminum each 3 mm in diameter. What is the resistance of the cable? A. 0.34 ohm B. 0.54 ohm C. 0.44 ohm D. 0.24 ohm

596. The resistance of a coil of wire is 1 kΩ at 20°C. If the coil is immersed into oil, the resistance falls to 880 Ω. If the wire has a temperature coefficient of 0.006 at 20°C, how much is the temperature of the liquid? A. 0°C B. -20°C C. 17.6°C D. none of these

613. One coulomb of charge is equal to the charge on __________ electrons. A. 628 x 10^16 B. 6.28 x 10^16 C. 62.8 x 10^16 D. 0.628 x 10^16

A lead conductor has a resistance of 25 n at 0 °C. Determine its resistance at -30 °C A. 22 Q B. 24 n C. 12 n D. 11 n

A neon glow lamp used as a night light ionizes at approximately A. 70 V B. 80 V A. Q2 /V C. 90 V D. 100 V

A resistor wound with a wire doubled back on itself to reduce the inductance. A. Bifilar resistor B. Wire-wound resistor C. Anti-inductive resistor D. Bleeder resistor

A series RL circuit has R of 10 Q and XL of 5 Q, its impedance in rectangular form is given by A. 10 + j s n B. 10 + j 10 Q C. 10 - j 5 Q D. 10 - j 10

A tank circuit is a A. Parallel LC circuit B. Series LC circuit C. A resonant circuit D. A non-resonant circuit

Barium-strontium titanite dielectric material is also called A. Ceramic B. Polyster C. Electrolytic D. Bakelite

Capacitance increase with A. Larger plate area and less distance between plates B. Larger plate area and greater distance between plates C. Smaller plate area and less distance between plates D. Higher values of applied voltage

Conventional flow assumes charges flow from A. Positive to negative B. Positive to positive C. Negative to positive D. Negative to negative

ECE Board Exam November 1995 578. _____ is the term used to express the amount of electrical energy in an electrostatic field. A. Joule B. Coulomb C. Volt D. Watt

ECE Board Exam November 1996 557. Electric charge of neutron is the same as __________. A. atom B. electron C. current D. proton

ECE Board Exam November 1997 531. Electric power refers to _________. A. volt ampere B. watt second C. volt coulomb D. joule

ECE Board Exam November 1998 530. In order to have a good conductor material, such material shall have __________ valence electrons. A. one B. five C. more than ten D. twenty one

How many coulombs are delivered by a storage battery in 25 hours if it is supplying current at the rate of 3 A? B. 2.592 x 103 C C. 2.592 x 108 C D. 2.592 x 1012 C 184. When frequen

If a coil has a Q of 10, it means that A. The energy stored in the magnetic field of the coil is 10 times the energy wasted in its resistance B. The energy wasted in its resistance is 10 times the energy stored in the magnetic field of the coil C. It is a low Q coil D. It is a high Q coil

If one resistance in a series connection is open, then A. The current is zero in all the other resistances B. The current is maximum in all the other resistances C. The voltage is zero across the open resistance D. The voltage is infinite across the open resistance

If resonant frequency is 10 kHz and quality factor is 50, then A. Bandwidth is 200 Hz B. XL = is 50,000n C. R is 50 n D. XC = is 50,000n

If three 9 mH inductors are connected in parallel without mutual inductance then the total inductance is A. 3 mH B. 9 mH C. 27 mH D. 18 mH

In a series RLC circuit A. The current lags VL by 90° B. The current leads VL by 90° C. XL leads Xc by90° D. Z = jXL at resonance

REE Board Exam March 1998 512. The resistance of a wire is 126.48 Ω at 100°C and 100 Ω at 30°C. Determine the temperature coefficient of copper at 0°C. A. 0.00427/°C B. 0.00615/°C C. 0.0256/°C D. 0.365/°C

REE Board Exam October 1998 507. A one-meter rod of 2-cm diameter is drawn until its resistance is 100 times the initial resistance. Its length afterwards is? A. 10 m B. 100 m C. 12.5 m D. 5 m

The rms value of a triangular or sawtooth waveform is times its peakvalue. A. 0.577 B. 0.500 C. 0.25 D. 0.707

The temperature coefficient of resistance of electrolytes is A. Negative B. Positive C. Zero D. Infinite

The temperature-resistance coefficient of pure gold is A. 0.0034 B. 0.0037 C. 0.0038 D. 0.0039

The usual load of a dc circuit is a/an A. Resistor B. Capacitor C. Inductor D. Both inductor and capacitor

Voltage resonance means A. Series resonance B. Parallel resonance C. Current magnification D. Gain magnification

What is considered as the most important value of a sine wave? A. Effective value B. Peak value C. Average value D. Instantaneous value

What is the most common non-sinusoidal waveform? A. Square wave B. Triangular wave C. Trapezoidal wave D. Sawtooth wave

What is the most convenient way of achieving large capacitance? A. By using multiplate construction B. By using air as dielectric C. By decreasing distance between plates D. By using dielectric of low permittivity

What is the peak factor for alternating current or voltage varying sinusiodally? A. 1.4142 B. 0.707 C. 0.636 D. 1.11

What is the reading of an ohmmeter for a shorted capacitor? A. Zero B. Infinity C. k n D. M n

What is the rms value of a square wave? A. Equals its peak value B. Equals its peak-to-peak value C. Peak divided by square root of two D. Peak divided by pi

What is the specific resistance of a pure germanium? A. 55 !!-cm B. 55 !2-m C. 55 !2-mm D. 55 k!2-m

What is the total effective capacitance of two 0.25 µF capacitors connected in series? A. 0.125 µF B. 1.25 µF C. 0.50 µF D. 2.5 if

What rating of a resistor determines its ability to absorb heat? A. Wattage B. Ohmic C. Current D. Voltage

When capacitors are connected in parallel, the total capacitance is A. Greater than the largest capacitor B. Smaller than the largest capacitor C. Smaller than the smallest capacitor D. Greater than the smallest capacitor

When capacitors are connected in series, the total capacitance is A. Smaller than the smallest capacitor B. Smaller than the largest capacitor C. Greater than any of the capacitor D. Greater than the largest capacitor

When frequency of an ac wave decreases, the value of XL in a coil A. Approaches zero B. Gets larger positively C. Gets larger negatively D. Stays constant

When two coils of identical reactance are in parallel without mutual inductance, the reactance of the combination is the reactance of each coil. A. One half B. Twice C. Four times D. One fourth

When two complex conjugates are subtracted, the result is a A. Quadrature component only B. Complex component C. In-phase component D. Real component

Which of the following describes the action of a capacitor? A. Stores electrical energy B. Opposes changes in current flow C. Creates a dc resistance D. Converts ac to dc

Which of the following does not refer to electrical energy? A. Volt-ampere B. Joule C. Watt-second D. Volt-coulomb

Which of the following has negative temperature coefficient? A. Carbon B. Nickel C. Brass D. Constantan

Which of the following is a common material used in wire-wound resistors? A. Manganin B. Carbon C. Bronze D. German silver wire

Which of the following is a disadvantage of a wire-wound resistor? A. It has reactance in radio-frequency circuits B. It cannot handle much power C. It draws a large amount of current D. It cannot handle high voltage

Which of the following is also known as anti-resonant circuit? A. Parallel resonant circuit B. Series resonant circuit C. Tuned circuit D. Tank circuit

Which of the following is neither a basic physical law nor deliverable from one? A. Ohm's law B. Coulomb's law C. Kirchhoff's first law D. Kirchhoff's second law

Which of the following is not a factor affecting dielectric strength? A. Mass B. Moisture content C. Temperature D. Thickness

Which of the following represents the energy stored in a capacitor? A. CV^2 /2 B. 2Q^2 IC C. C^2 IV D. CV

Which statement is true about a passive circuit? A. A circuit with neither a source of current nor a source of potential difference B. A circuit with a voltage source C. A circuit with a current source D. A circuit with only resistance as a load 111. What is a closed path made of several branches

Which waveform in which the rms value and the mean value are equal? A. Square wave B. Triangular wave C. Sine wave D. Sawtooth

332. A constant voltage source Vs = 60 is delivering a power to a series combination of R1 = 100 Ω, R2 = 200 Ω and R3 = 300 Ω. Calculate the voltage drop across R2. A. 10 V B. 20 V C. 30 V D. 40 V

339. Loop currents should be assumed to flow in which direction? A. Straight B. Either C or D arbitrarily selected C. Counter-clockwise D. Clockwise

383. A 220-volt, 60-Hz source is driving a series RL circuit. Determine the current in the circuit if R = 100 Ω and XL = 100 Ω. A. 1.10 A (lagging) B. 1.55 A (lagging) C. 2.20 A (lagging) D. 4.40 A (lagging)

384. How many electrical degrees a current will lead the voltage in a series RC load with R = 100 Ω and XC = 50 Ω? A. 13.28° B. 26.56° C. 31.72° D. 63.44°

388. A 200Ω resistor if connected in series with a capacitive reactance of 100 will give a total circuit impedance of A. 173.2 Ω B. 223.6 Ω C. 250.6 Ω D. 300.0 Ω

389. What will happen when the power factor of a circuit is increased? A. reactive power increases B. active power increases C. both active and reactive powers increases D. both active and reactive powers decreases

408. What is the resonant frequency of a circuit when L of 25 microhenry and C of 10 picofarad are in parallel? A. 63.7 MHz B. 10.1 MHz C. 63.7 kHz D. 10.1 kHz

439. If an AC signal has an average voltage of 18 V, what is the rms voltage? A. 12.726 V B. 19.980 V C. 25.380 V D. 16.213 V

441. Ignoring any inductive effects, what is the impedance of RC series capacitor made up of a 56K ohm resistor and a 0.33 uF capacitor at a signal frequency of 4650 Hz. A. 66730 ohms B. 57019 ohms C. 45270 ohms D. 10730 ohms

443. What is the relationship between frequency and the value of XC ? A. Frequency has no effect B. XC varies inversely with frequency C. XC varies indirectly with frequency D. XC varies directly with frequency

448. An alternating voltage is given by v = 20 sin 157 t. The frequency of the alternating voltage is A. 50 Hz B. 25 HZ C. 100 Hz D. 75 Hz

454. The active and reactive powers of an inductive circuit are equal. The power factor of the circuit is A. 0.8 lagging B. 0.707 lagging C. 0.6 lagging D. 0.5 lagging

462. A capacitor has a capacitance of 20 uF. The current supplied if it is placed across a 1100 V, 25 Hz supply. A. 3.554 A B. 6.91 A C. 3.45 A D. 9.61 A

468. What capacitance must be placed in series with an inductance of 0.05H, so that when the frequency is 100 Hz, the impedance becomes equal to the ohmic resistance? A. 70.5 uF B. 50.7 uF C. 5.7 uF D. 7.05 uF

487. A time of 10 ms is required for the current in an RL circuit to reach 90% of its final value. If R is 10 ohms, find the value of C to be inserted in series with the RL circuit so that the frequency of oscillation of the resulting current is 1000 cycles per second. A. 5.38 x 10-8 Farad B. 5.83 x 10-7 Farad C. 5.83 x 10-6 Farad D. 5.83 x 10-5 Farad

492. Consider a DC voltage source connected to a series RC circuit. When the steady state reaches, the ratio of energy stored in the capacitor to the total energy supplied by the voltage source is equal to A. 0.362 B. 0.500 C. 0.632 D. 1.00

622. The SI unit of specific resistance is _________. A. mho B. ohm-m C. ohm-m^2 D. ohm-cm

695. A resistor R is connected across a 120 V supply. A voltmeter of 10,000 ohms resistance is connected between the center of the resistor and one side of the supply and reads 40 V. What is the value of the resistance R? A. 10,000 ohms B. 20,000 ohms C. 30,000 ohms D. 40,000 ohms

696. A 240 V motor requiring 2,000 W is located 1 km from a power source. What diameter of copper wire is to be used if the power loss is to be kept 5%? A. 0.49 cm B. 0.54 cm C. 0.39 cm D. 0.35 cm

698. An arc lamp takes 10 A at 50 volts. A resistance R is to be place in series so that the lamp my burn correctly from a 110 V supply. Find the power wasted in this resistor. A. 800 watts B. 600 watts C. 700 watts D. 900 watts

699. A 20 Ω and 10 Ω resistors are connected in parallel and a 5 Ω resistor is connected in series with the parallel combination. The circuit is connected across a 48 V source with an internal resistance of 0.2. Calculate the current through the 5 Ω resistor. A. 5.57 amperes B. 4.04 amperes C. 3.58 amperes D. 7.63 amperes

7.For greater accuracy, the value of phase angle 0 should be determined from A. Cos 0 B. Tan 0 C. Sin 0 D. Sec 0

728. If a battery of 24 V is applied across terminals AB in Fig. 15.6, then power loss in 5 ohms resistor will be ________ electrical circuit figure 15.6 A. 180 W B. 45 W C. 90 W D. 24 W

734. If a battery of 12 V is applied across terminals 1 and 2 of Fig. 15.9, then current through 4 ohms resistor will be ________ electrical circuit figure 15.9 A. 1.5 A B. 3 A C. 2 A D. 2.5 A

806. EE Board Exam April 1988 A Barangay power station supplies 60 kW to a load over 2,500 ft, 100 mm^2, two-conductor copper feeder, the resistance of which is 0.078 ohm per 1000 ft. The bus bar voltage is maintained constant at 600 V. Determine the load current. A. 105 A B. 108 A C. 110 A D. 102 A

811. EE Board Exam April 1988 A barangay power station supplies 60 kW to a load over 2,500 ft of 0002-conductor copper feeder the resistance of which is 0.078 ohm per 1,000 ft. The bus bar voltage is maintained constant at 600 volts. Determine the maximum power which can be transmitted. A. 220.35 kW B. 230.77 kW C. 242.73 kW D. 223.94 kW

A law which states that when a constant electromotive force is applied to a circuit consisting of a resistor and capacitor connected in series, the time taken for the potential on the plates of the capacitor to rise to any given fraction of its final value depends only on the product of capacitance and resistance. A. Child's law B. CR law C. Coulomb's law D. Debye T3 law

A trigger circuit consisting of a capacitor of 0.01 µF is connected in series with a resistor. If the circuit requires 100 Vdc to operate, determine the value of the resistor when time constant is 0.009s. A. 900 Q B. 900 k!! C. 900 MQ D. 900 GQ

An inductive circuit of resistance 16.5 Q and inductance of 0.14 H takes a current of 25 A. if the frequency is 50 Hz, find the supply voltage. A. 1501 V B. 1174 V C. 1877 V D. 991 V

An inductive load always has a power factor A. Leading B. Lagging C. Zero D. Unity

In a circuit, a passive element is one which A. Supplies energy B. Receives energy C. Both supplies and receives energy D. Attenuates signal

In a parallel bank with unequal branch resistances A. The highest R has the highest I B. The lowest R has the highest V C. The lowest R has the highest V D. The highest R has the highest V

In adding or subtracting phasor quantities, form is the most convenient. A. Polar B. Rectangular C. Trigonometric D. Exponential

Norton's theorem is what form of an ac equivalent circuit? A. Voltage B. Current C. Both voltage and current D. Neither voltage nor current

REE Board Exam October 1996 510. What is the size in square millimeter (mm2) is the cable of 250 MCM size? A. 118.656 mm2 B. 126.675 mm2 C. 112.565 mm2 D. 132.348 mm2

REE Board Exam September 2002 521. One (1) kW is equal to __________ hp. A. 0.746 B. 1.34 C. 550 D. 1.5

REE Board Exam September 2003 519. In the American wire gauge, as the number of gauge increases, the diameter of wire ______________. A. increases B. decreases C. does not change D. become twice

Series resonant circuit is sometimes known as A. Rejector circuit B. Acceptor circuit C. Inductive circuit D. Capacitive circuit

The Q-factor of a parallel resonant circuit is also known as A. Current magnification factor B. Voltage magnification factor C. Load factor D. Leakage factor

The Q-factor of a parallel resonant circuit is also known as A. Voltage magnification factor B. Current magnification factor C. Gain magnification factor D. Resonance magnification factor

The average value of a triangular or sawtooth wave is times its peak value. A. 0.577 B. 0.500 C. 0.318 D. 0.637

The presence of an electric current is made known by A. Electric shock B. Effects produced C. Magnetic shock D. Flashing

What dielectric is generally employed by a variable capacitor? A. Mica B. Air C. Electrolyte D. Ceramic

What does a capacitor store? A. Voltage B. Charge C. Current D. Power

What is the peak factor of a triangular wave? A. 1.16 B. 1.73 C. 1.41 D. 1.11

What is the total capacitance of 10 capacitors, each of 20 µF in series? A. 200µF B. 2 µF C. 100 µF D. 0.5 µF

What is the value of a carbon composition resistor with the following color code: Brown, white, orange, red A. 190 Q; 10 % B. 19 kQ; 2 % C. 19 kQ; 20 % D. 1.9 kQ; 2 %

What maximum voltage can be applied across the capacitor for very short period of time? A. Working voltage B. Surge voltage C. Stray voltage D. Peak voltage

When current and voltage arte in phase in an ac circuit, the is equal to zero. A. Resistance B. Reactance C. Inductance D. Capacitance

When the movable plates of a gang capacitor completely overlap the fixed plates, the capacitance of the capacitor is A. Halfway between maximum and minimum B. Maximum C. Minimum D. Zero

When two in-phase sine waves that have identical frequency and amplitude are added together, then the result is a sine wave with the amplitude of either. A. Half B. Twice C. Four times D. One-fourth

When two unequal values of resistors are connected in parallel across a dc source, greater current flows through the A. Higher resistance B. Lower resistance C. Higher wattage resistance D. Lower wattage resistance

Which of the following dielectric materials makes the highest-capacitance capacitor? A. Air B. Barium-strontium titanite C. Mica D. Electrolyte

Which of the following is a preferred resistor value? A. 520 B. 47 C. 43,000 D. 54,321

Which of the following is a way of decreasing mutual inductance? A. Moving the coils closer B. Moving the coils apart C. Decreasing the number of turns of either coil D. Increasing the number of turns of either coil

Which of the following is not a factor affecting capacitance of a basic capacitor? A. Area of plates B. Number of plates C. Distance between plates D. Dielectric material used

Which of the following is the statement of Ohm's law? A. Electric current is directly proportional to both voltage and resistance B. Electric current varies directly as the voltage and inversely as the resistance C. Electrical power is directly proportional to the resistance and inversely as the current squared D. Electrical power is directly proportional to both voltage squared and the resistance

Which of the following materials has the lowest dielectric strength? A. Glass B. Paper C. Mica D. Teflon

he mutual inductance between two coils is the reluctance of magnetic path. A. Directly proportional to B. Inversely proportional to C. Independent to D. Equal to

301. The total resistance of a two similar wire conductors connected in parallel is ________. A. resistance of one wire multiplied by 4 B. same resistance of one wire C. one half the resistance of one wire D. double the resistance of one wire

328. How many 1 kΩ resistors to be connected in parallel are needed in order to get 100 Ω? A. 2 B. 5 C. 10 D. 20

355. Theorem used in simplifying circuit analysis by considering the effect of supply voltages one at a time. A. Thevenin's theorem B. Norton's theorem C. Superposition D. KVL

361. When can an ac-voltage, v = 120sin120πt reach its first peak? A. 4.167 μs B. 8.334 μs C. 4.167 ms D. 8.334 ms

376. In a purely inductive circuit the current A. leads the voltage by 45° B. leads the voltage by 90° C. lags the voltage by 90° D. lags the voltage by 45°

380. The impedance in the study of electronics is represented by resistance and ________. A. inductance and capacitance B. inductance C. reactance D. capacitance

431. Two current sources deliver to a common load. The first source delivers current whose equation is 25sin 100πt A while the second delivers a current whose equation is 15 cos 100πt A. What is the rms values of the current in the load? A. 29.15 A B. 40 A C. 20.6 A D. 10 A

432. It is a rotating sector that represent either current or voltage in an AC circuit. A. Resistance B. Phasor C. polar diagram D. velocity

434. Find the phase angle between the voltage across through the circuit when Xc is 25 ohms, R is 100 ohms and XL is 50 ohms. A. 76 deg with the voltage leading the current B. 24 deg with the voltage lagging the current C. 14 deg with the voltage leading the current D. 76 deg with the voltage lagging the current

435. Calculate the period of an alternating current having a equation of I=20sin 120πt A. 4.167 ms B. 8.33 ms C. 16.67 ms D. 33.33 ms

445. There are no transients in pure resistive circuits because they A. Offer high resistance B. Obey ohm's Law C. Are linear circuits D. Have no stored energy

453. An R-L series ac circuit has 15 V across the resistor and 20 V across the inductor. The supply voltage is A. 35 V B. 5 V C. 25 V D. 175 V

497. In a circuit the voltage across an element is v(t) = 10 (t - 0.01)e-100t V. The circuit is A. un-damped B. under damped C. critically damped D. Over damped

610. If the number of valence electrons of an atom is more than 4, the substance is usually __________. A. a semiconductor B. a conductor C. an insulator D. none of these

614. One cc of copper has about ___________ free electrons at room temperature. A. 200 B. 20 x 10^10 C. 8.5 x 10^22 D. 3 x 10^5

671. ECE Board Exam November 1999 The total resistance of a two similar wire conductors connected in parallel is __________ A. same resistance of one wire B. double the resistance of one wire C. one half the resistance of one wire D. resistance of one wire multiplied by 4

674. ECE Board Exam April 1998 Ohm's law refers to __________. A. power is directly proportional to both voltage squared and the resistance B. power is directly proportional to the resistance and inversely as the current squared C. current varies directly as the voltage and inversely as the resistance D. current is directly proportional to both voltage and resistance

679. ECE Board Exam April 2000 A series circuit in which desired portions of the source voltage may be tapped off for use equipment. A. Voltage trap B. Voltage selector C. Voltage divider D. Dividing network

681. ECE Board Exam November 1997 How much power does an electronic equipment consume, assuming a 5.50 amperes current flowing and a 120 volts power source? A. 125.5 watts B. 66 watts C. 660 watts D. 60 watts

701. The hot resistance of an incandescent lamp is 10 ohms and the rated voltage is 50 V. Find the series resistance required to operate the lamp from an 80 V supply. A. 8 ohms B. 4 ohms C. 6 ohms D. 10 ohms

733. The total resistance between terminals 1 and 2 of the circuit shown in Fig. 15.9 is _______ electrical circuit figure 15.9 A. 12 ohms B. 2.67 ohms C. 2 ohms D. 64 ohms

735. The resistance between terminals 1 and 2 of Fig. 15.10 is _________ electrical circuit figure 15.10 A. 12 ohms B. 8 ohms C. 16 ohms D. 3 ohms

888. The load resistance needed to extract maximum power from the circuit of Fig. 18.6 is _______ ohm. electrical circuit figure 18.6 A. 2 ohms B. 9 ohms C. 6 ohms D. 18 ohms

899. What do you call the head to tail connection of two or more op-amp circuits wherein the output of one op-amp is the input of another op-amp? A. Parallel Op-Amps B. Follow-Thru Connection C. Cascade Connection D. Series Op-Amps

A 5 µF capacitor charge to 5V has a stored charge equal to A. 1 µc B. 5 µc C. 25 µC D. 200 µc

A capacitor consists of two A. Conductors only B. Dielectric only C. Conductors separated by a dielectric D. Dielectric separated by a conductor

A capacitor of 0.5 µF charged to 220 V is connected across an uncharged 0.5 µF capacitor. What is the voltage across each capacitor? A. 220 V B. 150 V C. 110 V D. 22 V

ECE Board Exam November 1998 584. If the bands on a resistor are red, red, orange and silver, what is the resistance value? A. 220 ohms 5% B. 223 0hms 10% C. 22,000 ohms 10% D. 2200 ohms 20%

ECE Board Exam November 1999 550. Which material has more free electrons? A. mica B. insulator C. conductor D. dielectric

If a certain circuit has a current that is lagging the voltage by 45°, then it displays A. Pure inductive reactance B. Resistance and capacitance reactance C. Resistance and inductive reactance D. Pure capacitive reactance

If a multiplate capacitor has 10 plates, each of area 10 cm 2 , then A. 10 capacitors will be in parallel B. 10 capacitors will be in series C. 9 capacitors will be in parallel D. 9 capacitors will be in series

If an emf in circuit A produces a current in circuit B, then the same emf in circuit B produces the same current in circuit A. this theorem is known as A. Maximum power transfer theorem B. Millman's theorem C. Reciprocity theorem D. Norton's theorem

If the inductance is decreased, the impedance of the circuit containing a resistor a capacitor and an inductor connected in series to an ac source A. Decreases B. Increases C. Decreases or increases D. Decreases, increases or remains the same

In a complex resistance-reactance plane, XL isrepresented A. By an axis opposite the R axis B. By an axis perpendicular to the XC axis C. By an axis opposite the XC axis D. By an axis parallel to the R axis

In a rectangular wave, the form factor is A. 1.11 B. 1.16 C. 1.0 D. 1.73

In a series RLC circuit A. Increasing the frequency decreases the resistance B. Increasing the frequency increases the resistance C. Both XL and XC change as frequencychanges D. Impedance will always decrease

REE Board Exam October 1999 517. What is the power required to transfer 97,000 coulombs of charge through a potential rise of 50 volts in one hour? A. 0.5 kW B. 0.9 kW C. 1.3 kW D. 2.8 kW

The capacitor opposes any change in voltage across it by A. Passing a voltage proportional to the rate of change of current B. Acting as a short circuit at time equal to zero C. Passing a current proportional to the rate of change of voltage D. Acting as a short circuit at time equal to infinityC

The internal resistance of an ideal voltage source is A. Infinite B. Equal to the load resistance C. Zero D. To be determined

What increases the resistance of wire at high frequencies? A. Temperature B. Voltage C. Skin effect D. Insulation

What is expected when two 20 kn, 1 watt resistor in parallel are use instead of one 10 kn, 1 watt? A. Provides higher current B. Provides less power C. Provides more power D. Provides wider tolerance

What is the half-power bandwidth of a parallel resonant circuit which has a resonant frequency of 3.6 MHz and Q of 218? A. 1.65 kHz B. 16.5 MHz C. 16.5 kHz D. 165 kHz

What is the hot resistance of a 100 W, 220 V incandescent lamp? A. 2.2 n B. 22 n C. 484 n D. 4.84 n

What is the purpose of a load in an electric circuit? A. To increase the circuit current B. To decrease the circuit current C. To utilize electrical energy D. To make the circuit complete

What is the reciprocal of capacitance? A. Reluctance B. Susceptance C. Elastance D. Conductance

What is the total resistance of a two equal valued resistors in series? A. The difference of both B. The product of both C. Twice as one D. The sum of their reciprocals

When two pure sine waves of the same frequency and the same amplitude which are exactly 180° out-of-phase are added together, the result is A. A wave with twice the amplitude B. A wave with half the amplitude C. Zero signal D. A wave with twice the frequency

Which component opposes voltage change? A. Resistor B. Inductor C. Capacitor D. Transistor

167. ECE Board Exam April 2000 Refers to the most important components in controlling flow of electrons A. voltage, electromotive force and current B. reactance, current and resistance C. conductance, resistance and reactance D. voltage, resistance and current

312. Factors that determine the capacitance of a capacitor. A. area of the plate; directly proportional B. distance between plate; inversely proportional C. dielectric constant; directly proportional D. all of these

322. In electrical circuits, current is known as the flow of charged carriers, such as electrons. When can this happen? A. when an electrical force (called emf) is applied B. when material used allows electrons to flow C. when there is circuit continuity D. all of the above

327. A shunt resistor is used to limit the load current to 0.5 A, if the load resistance is 100 Ω and the original current is 1amp, what should be the value of the shunt resistance? A. 25 Ω B. 50 Ω C. 75 Ω D. 100 Ω

341. In a mesh, the algebraic sum of all voltages and voltage drops is equal to zero. A. superposition theorem B. Norton's law C. Kirchhoff's first law D. Kirchhoff's second law

359. Advantage(s) of ac over dc A. economically produced B. transmission of ac is more efficient C. ac voltages can be easily changed D. all of the above

367. At what angle does an alternating voltage of cosine-waveform reaches its negative peak? A. 45° B. 90° C. 135° D. 180°

371. What do you mean by root-mean-squared (rms) value? A. it is the average value B. it is the effective value C. it is the value that causes the same heating effect as a dc-voltage D. B or C

393. A 6-Ω resistor is connected in series with a capacitive reactance of 8 Ω. If the supply voltage is 200 V, what is the apparent power of the circuit? A. 1200 W B. 2400 W C. 3200 W D. 4000 W

489. A series RLC circuit has R = 200 Ω, L = 0.1 H and a capacitor C = 10 μF. If a 100 V dc source is connected across the terminals of the series circuit at t = 0, determine the current after 1 millisecond. Assume zero initial conditions. A. 0.353 A B. 0.229 A C. 0.253 A D. 0.368 A

490. Double energy transient are produced in circuits consisting of A. two or more resistors B. resistance and inductance C. resistance and capacitance D. resistance, inductance and capacitance

500. A series R-C circuit has a capacitor with an initial voltage of 11 V. A 15 V dc source is now connected across the R-C circuit. The initial rate of change of capacitor voltage can be A. 15 Χ 0.368 / RC B. 15Χ 0.632 / RC C. 11/RC D. 4/RC

571. How much is the resistance of a germanium slag 10 cm long and cross sectional area of 1 square cm? A. 55 k ohms B. 5.5 k ohms C. 550 k ohms D. 550 ohms

643. Which of the following material has nearly zero temperature-coefficient of resistance? A. carbon B. porcelain C. copper D. manganin

709. Electrical appliances are connected in parallel because it _________ A. is a simple circuit B. draws less current C. results in reduce in power loss D. makes the operation of appliances independent of each other

720. The current in 4.5 ohms resistor in Fig. 15.4 will be _________. electrical circuit figure 15.4 A. 3.5 A B. 3 A C. 2 A D. 2.5 A

749. If in Fig. 15.15, resistor R2 becomes open-circuited, the reading of the voltmeter will become electrical circuit figure 15.15 A. zero B. 150 V C. 50 V D. 200 V

754. In the series circuit of Fig 16.2, the value of V0 is ___________ volt. electrical circuit figure 16.2 A. 12 B. -12 C. 0 D. 6

794. A force of 10,000 N accelerates a body to velocity 0.1 km/s. The power developed is __________ kW. A. 1,000,000 B. 36,000 C. 3600 D. 1000

864. For maximum power transfer, the relation between load resistance RL and internal resistance Ri of the voltage source is _________. A. RL = 2Ri B. RL = 0.5Ri C. RL = 1.5Ri D. RL = Ri

866. The open-circuited voltage at terminals of load RL is 30 V Under the conditions of maximum power transfer, the load voltage would be _________. A. 30 V B. 10 V C. 5 V D. 15 V

891. If two identical 3 A, 4 Ω Norton equivalent circuits are connected in parallel with like polarity to like, the combined Norton equivalent circuit is A. 6 A, 4 Ω B. 6 A, 2 Ω C. 3 A, 2 Ω D. 6 A, 8 Ω

893. Two identical 3 A, 1 Ω batteries are connected in parallel with like polarity with like polarity to like. The Norton equivalent circuit of the combination is A. 3 A, 0.5 Ω B. 6 A, 1 Ω C. 3 A, 1 Ω D. 6 A, 0.5 Ω

895. For a linear network containing generators and impedance, the ratio of the voltage to the current produced in other loop is the same as the ratio of voltage and current obtained when the positions of the voltage source and the ammeter measuring the current are interchanged. This network theorem is known as _________ theorem. A. Millman's B. Norton's C. Tellegen's D. Reciprocity

A capacitor requires 12 µC of charge to raise its potential of 3 V. What is the capacitance of the capacitor? A. 36 µF B. 15 µF C. 0.25 µF D. 4µF

A factor that states how much the resistance changes for a change in temperature? A. Resistivity B. Specific resistance C. Coefficient of temperature change D. Temperature coefficient of resistance

At parallel resonance, the currents flowing through L and C are A. Infinite B. Zero C. Unequal D. Equal

ECE Board Exam April 1998 558. Ion is _________. A. free electron B. nucleus without protons C. proton D. an atom with unbalanced charges

ECE Board Exam April 1998 560. What is the value of a resistor with colors from left: Orange, Blue, Gold and Silver? A. 34 ohms + /-10% B. 36 ohms +/-10% C. 3.4 ohms +/-10% D. 3.6 0hms +/-10%

ECE Board Exam April 1998 589. Which of the following does not refer to electric energy? A. Joule B. Watt second C. Volt coulomb D. Volt ampere

ECE Board Exam November 1996 564. Electric energy refers to _________. A. Joules divided by time B. Volt-ampere C. Watt D. Volt-coulomb

ECE Board Exam November 1999 554. The definite discrete amount of energy required to move an electron from a lower shell to higher shell. A. quantum B. positive energy C. negative energy D. quanta

ECE Board Exam November 2000 586. The energy in an electron that is called the energy of position A. Kinetic energy B. Kinematics C. Electromotive force D. Potential energy

EE Board Exam April 1995 509. A certain wire has a resistance R. The resistance of another wire identical with the first except for having twice its diameter is A. 4R B. R/2 C. 2R D. R/4

EE Board Exam October 1991 513. Two heating elements which is 500 ohms and 250 ohms are connected in series with temperature coefficients of 0.001 and 0.003 ohms per °C, respectively at 20°C. Calculate the effective temperature coefficient of the combination. A. 0.00215 B. 0.00626 C. 0.00712 D. 0.00167

If voltage across the plates of 2 F capacitor is increased by 4 V, then charge on the plates will A. Decrease by 2 C B. Increase by 2 C C. Decrease by 4 C D. Increase by 4 C

Liquids that are good conductors because of ionization are called A. Electrolytic B. Bases C. Acid D. Electrolytes

Loop currents should be assumed to flow in which direction A. Straight B. Clockwise C. Counter-clockwise D. Either B or C arbitrarily selected

REE Board Exam October 1999 516. How long must a current of 5 A pass through a 10 ohm resistor until a charge of 12000 coulomb passes through? A. 1 min B. 2 min C. 3 min D. 4 min

REE October 1997 502. Determine the resistance of a busbar made of copper if the length is 10 meters long and the cross section is a 4 x 4 cm2. Use 1.7241 micro ohm-cm as the resistivity. A. 2.121 x 10-4 Ω B. 4.312 x 10-4 Ω C. 3.431 x 10-5 Ω D. 1.078 x 10-4 Ω

Refers specifically to steady state values of quantities in ac circuits which are complex numbers. A. Domain B. Scalar quantity C. Vector quantity D. Phasor quantity

The admittance of a parallel RLC circuit is found to be the sum of conductance and susceptances. A. Algebraic B. Arithmetic C. Vector D. Phasor

The charging of a capacitor through a resistance follows what law? A. Linear law B. Hyperbolic law C. Inverse-square law D. Exponential law

The curve between current and frequency is termed as A. Voltage curve B. Gain curve C. Power curve D. Resonance curve

The impedance in the study of electronics is represented by resistance and A. Inductance B. Capacitance C. Inductance and capacitance D. Reactance

The open-circuit voltage at the terminal of load RL is 60V. Under the condition of maximum power transfer, the load voltage will be A. 60 V B. 15 V C. 20 V D. 30 V

The power factor of a circuit is equal to A. RZ B. XC/Z C. XL/Z D. R/Z

What is a closed path made of several branches of the network called? A. Junction B. Node C. Terminal D. Loop

What is a rotating vector whose projection can represent either current or voltage in an ac circuit? A. Polar diagram B. Scalar quantity C. Velocity D. Phasor

What is the complex impedance of a circuit with an absolute resistance of 300 Q? A. 0 + j 300 Q B. 300 + j 90 Q C. 0 - j 300 Q D. 300 + j 0 n

What is the cross-sectional are of a conductor whose diameter is 0.001 inch? A. One micron B. One angstrom C. One steradian D. One circular mil

What refers to such work at very low temperatures, near absolute zero? A. Cryogenics B. Superconductivity C. Subsonic D. Thermionic

What theorem is usually used in the analysis of transistor circuit? A. Superposition theorem B. Millman's theorem C. Thevenin's theorem D. Norton's theorem

What value of R is needed with a 0.05 µF C for an RC time constant of 0.02 s? A. 400 n B. 400 Mn C. 400 Gn D. 400 k!!

Which factor does not affect resistance? A. Length B. Resistivity C. Cross-sectional area D. Mass

Which of the following capacitors are used only in dc circuits? A. Mica B. Ceramic C. Mylar D. Electrolytic

Which of the following capacitors has the highest cost per µF? A. Plastic B. Air C. Mica D. Electrolytic

Which of the following capacitors is suitable for dc filter circuits? A. Mica B. Ceramic C. Paper D. Electrolytic

Which of the following combination of length and cross-sectional area will give a certain volume of copper the least resistance? A. 2L and1/2 A B. Does not matter because the volume of copper remains the same C. L and A D. ½ L and 2 A

With double the number of turns by the same length and area, the inductance is A. The same B. Doubled C. Quartered D. Quadrupled

. The ratio of W/VA in an ac circuit means A. Power factor D. 90o B. Reactive factor C. Quality factor D. Load factor

356. Three resistors, R1 = 60 Ω, R2 = 80 Ω and R3 = 100 are connected in delta. If the network is to be transformed into star, what would be the value of the resistor opposite of R2? A. 25.0 Ω B. 33.3 Ω C. 45.0 Ω D. 56.7 Ω

358. Most ac-supplies are in the form of A. sine-wave B. square-wave C. triangular-wave D. rectangular-wave

379. The reactance of a 25 mH coil at 500 Hz is which of the following? A. 785 ohms B. 785,000 ohms C. 13 ohms D. 0.0013 ohms

625. The SI unit of conductance is _______. A. mho B. ohm C. ohm-m D. ohm-cm

765. Which of the following is a non-linear element? A. diode B. heater coil C. transistor D. electric arc with unlike electrode

809. EE Board Exam April 1992 In Manila, the LRT runs between Gil Puyat Station and Tayuman Station, which is 4 km apart and maintains voltages of 420 volts and 410 volts respectively. The resistance of go and return is 0.05 ohm per km. The train draws a constant current of 300 A while in motion. What are the currents supplied by the two stations if the train is at the distance of minimum potential? A. 175 A, 125 A B. 183 A, 117 A C. 164 A, 136 A D. 172 A, 123 A

810. EE Board Exam October 1986 An LRT car, 5 km distance from the Tayuman station, takes 100 A over a 100 mm hard drawn copper trolley wire having a resistance of 0.270 ohm per km. The rail and ground return has a resistance of 0.06 ohm per km. If the station voltage is 750 V, what is the efficiency of transmission? A. 78% B. 81% C. 74% D. 79%

814. EE Board Exam October 1991 Twelve identical wires each of resistance 6 ohms are arranged to form the edge of a cube. A current of 40 mA is led into the cube at one corner and out at the other diagonally opposite corners. Calculate the potential difference developed between these corners. A. 0.20 V B. 0.28 V C. 0.22 V D. 0.24 V

815. EE Board Exam August 1976 Find the value of the voltage V. electrical circuit figure 17.1 A. 12.34 V B. 11.24 V C. 12.19 V D. 11.66 V

816. EE Board Exam April 1982 Referring to the circuit diagram below, if the charger voltage is 130 volts and the battery voltage is 120 volts, solve for the current Ib. electrical circuit figure 17.2 A. -0.215 A B. 0.215 A C. -0.306 A D. 0.306 A

886. While calculating Rth, constant -current sources in the circuit are A. replaced by "opens" B. replaced by "shorts" C. treated in parallel with other voltage sources D. converted into equivalent voltage sources

887. Thevenin resistance of the circuit of Fig. 18.5 across its terminals A and B is ______ ohm. electrical circuit figure 18.5 A. 6 ohms B. 3 ohms C. 9 ohms D. 2 ohms

A capacitive load always has a power facto A. Leading B. Lagging C. Zero D. Unity

A capacitor is basically constructed of A. Two conductors separated by a dielectric B. Two dielectric separated by a conductor C. Conductors and dielectric D. Conductors and semiconductors

A capacitor is used to A. Block dc current B. Pass dc current C. Open voltage source D. Short the voltage source

A capacitor opposes change in A. Voltage B. Current C. Voltage and current D. Neither voltage nor current

ECE Board Exam April 2001 539. What is a symbol that represents a quantity or a single object? A. unit B. number C. item D. base

For a linear circuit, voltage or current is used to calculate average power. A. Rms B. Peak C. Average D. Instantaneous

If the output resistance of a voltage source is 4 Q, it internal resistance should be A. 4 n B. 8 Q C. 2 Q D. Infinite

If two complex conjugates are added, components results. A. In-phase B. Quadrature C. Complex D. Out-of-phase

Rationalizing the denominator of a complex number means A. Eliminating the j component in the denominator B. Adding j component in the denominator C. Eliminating the j component in the numerator D. Adding j component in the numerator

The Q-factor of a parallel resonant circuit is also known as A. Current magnification factor B. Voltage magnification factor C. Load factor D. Leakage factor

The arc across a switch when it open an RL circuit is a result of the A. Large self-induced voltage across L B. Long time constant C. Low resistance of the open switch D. Surge of resistance

The reactance curve is a plot of frequency versus for a series RLC circuit A. Current B. Voltage C. Gain D. Impedance

Transient period is considered over after A. 5 T B. 1 r C. 100 r D. 6 r

314. Which of the following describes the action of a capacitor? A. Converts ac into dc B. Stores electrical energy C. Opposes change in current flow D. Creates a dc resistance

323. What utilizes electrical energy in electrical circuits? A. supply emf B. load C. the conducting wires D. all of the above

325. A 50 Ω resistor is connected in series with a 150C resistor and to a supply voltage of 20 V. What is the current through the 50 Ω resistor? A. 0.01 A B. 0.1 A C. 1.0 A D. 10 A

329. Two resistors, R1 = 100 Ω and R2 = 200 Ω are connected in series, if the voltage across R2 is 20 V, what is the voltage across R1? A. 5 V B. 10 V C. 15 V D. 20 V

331. A 6A current source drives a load consisting a parallel combination of R1 = 50 Ω and R2 = 25 Ω. Determine the current I1 through R1. A. 1 amp B. 2 amps C. 3 amps D. 4 amps

471. The __________ the Q of a circuit, the narrower the bandwidth. A. Lower B. Higher C. Broader D. Selective

472. A 5 microfarad capacitor is discharged suddenly through a coil having an inductance of 2 H and a resistance of 200 ohms. The capacitor is initially charge to a voltage of 10 volts. Find the additional resistance required just to be prevent oscillation. A. 1625 ohms B. 1065 ohms C. 1265 ohms D. 1025 ohms

697. Three resistors of 10, 12 and "x" ohms, respectively are connected in parallel across a constant current source of 8 A. Determine "x" if this resistor draws 2.5 A. A. 10 Ω B. 12 Ω C. 13 Ω D. 11 Ω

829. In the Norton's equivalent circuit, the source is a A. constant voltage source B. constant current source C. constant voltage, constant current D. none of these

830. The superposition theorem requires as many circuits to be solved as there are A. meshes B. source C. nodes D. all of these

833. An active element in a circuit is one which _________. A. receives energy B. supplies energy C. both receives and supplies energy D. none of these

A capacitance of 0.05 µF equals A. 0.05 x 106 F B. 0.05 x 10-6 F C. 0.05 x 10-12 F D. 0.05 x 1012 F

ECE Board Exam November 1999 536. What is the basic unit for measuring current flow? A. coulomb B. ampere C. volt D. atomic weight

ECE Board Exam November 2001 568. Which type of variable resistor should you use for controlling large amount of current? A. Potentiometer B. Adjustable wirewound C. Variac D. Rheostat

ECE Board Exam November 2001 572. A variable resistor normally used as a voltage divider A. Carbon film resistor B. Potentiometer C. Adjustable resistor D. Metal film resistor ECE Board Exam April 2001

EE Board Exam October 1991 503. One turn of a copper bar is produced by cutting copper washer along a radius and spreading the ends. The washer is cut from soft drawn copper having a resistivity at 20°C of 1.732 x 10-6 ohm-cm. The washer is 0.125 inch thick and has inside diameter and outside diameter of 1 inch and 9 inches respectively. Calculate the exact resistance between the two ends of the turn to direct current, taking into account the non-uniform current distribution. Assume the contact along the ends of the turn to be perfect over the entire cross section. A. 12.74 x 10-6 Ω B. 15.53 x 10-6 Ω C. 17.22 x 10-6 Ω D. 14.83 x 10-6 Ω

For a series circuit, the higher the quality factor A. The greater the bandwidth B. The narrower the passband C. The broader the resonance curve D. The wider the passband

For a triangular and sawtooth waveform the rms voltage or current equals A. 0.707 times peak value B. 0.577 times peak value C. 0.577 times average value D. 0.707 times rms value

For series capacitors, total charge is A. The sum of individual charges B. Equal to the charge of either capacitors C. Equal to the product of the charges D. The quotient of the charges

321. With the same voltage applied, which of the following allows more current? A. 25 ohms B. 250 ohms C. 0.25 ohms D. 2.5 ohms

362. Calculate the period of an alternating current having an equation of I = 20sin120πt. A. 4.167 ms B. 8.33 ms C. 16.67 ms D. 33.33 ms

364. An alternating voltage of sine-wave form has a maximum voltage of 311V. What is its value at 225°? A. 110 V B. 220 V C. -220 V D. -110 V

390. A series RL network is supplied with a 200-volt, 60-cycle source. If the voltage across the resistor R is 100 V, what is the voltage across the inductor L? A. 0 V B. 100 V C. 173.2 V D. 200 V

395. A series RC circuit has an apparent power of 4000 W. If R = 6 Ω, and XC = 8 Ω, determine the reactive power. A. 1200 W B. 2400 W C. 3200 W D. 4000 W

396. A network has a true power and a reactive power of 2400 W and 3200 W respectively. What is its apparent power? A. 800 W B. 1600 W C. 4000 W D. 5600 W

399. A parallel RL circuit with R = 60 Ω, and XL = 40 Ω has a total impedance of A. 24.3 Ω B. 28.3 Ω C. 33.3 Ω D. 38.3 Ω

411. What is the cause of a minimum Q on a single-tuned LC circuit? A. decreased series resistor B. decreased shunt resistor C. increased shunt resistor D. decreased capacitance

420. Absolutely, when can we say that the circuit is at resonance? A. when XL = XC B. when the current is minimum C. when the voltage and current are in-phase D. all of the above

456. An AC circuit has a resistance of 6 ohms, inductive reactance of 20 ohms, and capacitive reactance of 12 ohms. The circuit power will be A. 0.8 lagging B. 0.8 leading C. 0.6 lagging D. 0.6 leading

493. An inductor at t = 0 with initial current I0 acts as A. short B. open C. current source D. voltage source

797. One watt is equal to ___________. A. 4.19 cal/sec B. 778 BTU/sec C.10^7 ergs/sec D. 10^-7 ergs/sec

EE Board Exam April 1989 515. It is required that a loading of 3 kW be maintained in a heating element at an initial temperature of 20°C, a voltage of 220 V is necessary for the purpose. After the element has settled down to steady state, it is found that a voltage of 240 volts is necessary to maintain the 3 kW loading. The element resistance temperature coefficient is 0.0006 per degree centigrade at 20°C. Calculate the final temperature of the heating element. A. 345.43°C B. 326.42°C C. 336.84°C D. 318.48°C

EE Board Exam October 1990 504. Determine the resistance of a conductor 0.10 m long, with a uniform diameter of 1.0 cm and having a resistivity which varies as a function of length L measured from the one end of the conductor according to ρ = 0.003 + 10-4 L2 ohm-cm. A. 0.0852 ohm B. 0.0915 ohm C. 0.0806 ohm D. 0.0902 ohm

EE Board Exam October 1992 514. The insulation resistance of a kilometer of the cable having a diameter of 2 cm and an insulation thickness of 2 cm is 600 ohms. If the thickness of the insulation is increased to 3 cm, find the insulation resistance of the cable. A, 725 ohms B. 850 ohms C. 757 ohms D. 828 ohms

In an ac circuit, the power dissipated as heat depends on A. Impedance B. Capacitive reactance C. Resistance D. Inductive reactance

Kirchhoff's laws (KCL and KVL) are applicable to A. DC circuits B. AC circuits C. DC as well as AC circuits D. Passive networks alone

Property of an electric circuit that dissipates electric energy A. Reactance B. Impedance C. Resistance D. Conductance

REE Board Exam April 2001 526. A certain generator generates 1,500,000 joules per minute. What is the output in kW? A. 50 B. 500 C. 25 D. 125

The graph between an alternating quantity and time is called A. Sine wave B. Curve C. Waveform D. A plot

What refers to the lowest voltage across any insulator that can cause current flow? A. Conduction voltage B. Critical voltage C. Breakdown voltage D. Voltage capacity

When the power factor of a circuit is zero, A. Power absorbed is maximum B. Power absorbed is minimum C. Power absorbed is zero D. The impedance is minimum

Which of the following dielectric materials makes the lowest-capacitance capacitor? A. Paper B. Mica C. Air D. Electrolyte

Which of the following does not affect resistance? A. Resistivity B. Cross-sectional area C. Mass D. Length

Which of the following is not considered a physical factor affecting resistance? A. Length B. Material type C. Temperature D. Cross-sectional

Which of the following is the peakiest? A. Square wave B. Sinusoidal wave C. Triangular wave D. Rectangular wave

Which of the statements below is not true? A. Current source is an active element B. Resistor is a linear element C. Voltage source is a passive element D. Diode is a non-linear element

Which statement is true? A. A series resonant circuit is of high impedance B. A parallel resonant circuit is of low impedance C. A series resonant circuit is inductive if it operates at a frequency higher than the resonant frequency D. A parallel resonant circuit is inductive if it operates at a frequency higher than the resonant frequency

306. When resistors are connected in series, what happens? A. The effective resistance is decreased B. Nothing C. The tolerance is decreased D. The effective resistance is increased

307. A 33 kilo ohms resistor is connected in series with a parallel combination made up of a 56 kilo ohm resistor and a 7.8 kilo ohm resistor. What is the total combined resistance of these three resistors? A. 63769 ohms B. 49069 ohms C. 95800 ohms D. 39067 ohms

344. Considered as the reverse of Thevenin's theorem. A. Maxwell B. Superposition C. Kirchhoff D. Norton's

605. The number of compounds available in nature is ___________. A. 105 B. 300 C. 1000 D. unlimited

851. The value of Rth in Fig. 17.9(b) is _________. electrical circuit figure 17.9 A. 15 Ω B. 3.5 Ω C. 6.4 Ω D. 7.4 Ω

A series RLC circuit has a power factor at its half-power points A. Unity B. Leading C. Lagging D. Either B or C

ECE Board Exam November 1998 583. Resistor with colored bands in the body A. Adjustable resistor B. Wire-wound resistor C. Variable resistor D. Carbon composition resistor

In a rectangular wave, the peak factor is A. 1.16 B. 1.73 C. 1.11 D. 1.0

706. A d.c. circuit usually has _________ as the load. A. resistance B. inductance C. capacitance D. both inductance and capacitance

867. The maximum power transfer theorem is used in _________. A. electronic circuits B. power system C. home lighting circuits D. none of these

898. Find the equivalent resistance between terminals a and b of the circuit shown. Each resistance has a value of 1 ohm. electrical circuit figure 18.8 A. 5/6 ohms B. 5/11 ohms C. 5/14 ohms D. 5/21 ohms

ECE Board Exam November 1997 576. Rust in electrical (wire) connections will result to __________. A. Conductance B. Resistance C. Voltage D. Inductance

The maximum power transfer theorem is used in A. Power system B. Electronic system C. Refrigeration D. Air conditioning

What is the resonant frequency of a circuit when L of 25 microhenrys and C of 10 picofarads are in parallel? A. 10.1 kHz B. 10.1 MHz C. 101 MHz D. 101 kHz

Which of the following has a positive temperature coefficient? A. Mica B. Manganin C. Silicon D. Carbon

2.What theorem is generally used in the analysis of vacuum tubes? A. Superposition theorem B. Millman's theorem C. Thevenin's theorem D. Norton's theorem

319. Which of the following characterizes inductance? A. Tends to oppose dc B. Tends to oppose changes in voltage C. Tends to oppose changes in current D. Opposes all frequencies equally

370. Determine the effective voltage of v = 100sin120πt. A. 31.80 V B. 35.35 V C. 70.71 V D. 90.00 V

An impedance given by 90L-45° is a/an impedance. A. Inductive B. Conductive C. Resistive D. Capacitive

Points to be considered in choosing a capacitor A. Working voltage B. Type of dielectric C. Capacitance D. All of the above

Series resonance occurs when A. XL = XC B. XL = R C. Z = R D. Both A and C

. A capacitance of 6 µµF means A. 6 pF B. 6 nF C. 6 fF D. 6 aF

303. Determine the value of a resistor with colors from left to right; Brown, Green, Gold, and Silver. A. 1.5 ohms ± 10% B. 15 ohms ± 10% C. 1.5 ohms ± 20% D. 15 ohms ± 20%

687. ECE Board Exam November 1999 A condition in which the heat in of around the circuit increases beyond or to a higher than normal level. A. Excessive heat condition B. Open condition C. Direct short D. Grounded

An inductance of 1 mH is A. 0.001 H B. 0.01 H C. 0.0001 H D. 0.10 H

The value of temperature coefficient (a) is dependent upon A. The nature of material and temperature B. The length of material C. The cross-sectional area of the material D. The volume of the material

Tungsten filament of bulbs has a hot resistance higher than its cold resistance due to its temperature coefficient which is A. Positive B. Negative C. Zero D. Infinite

VL = VC in a series RLC circuitwhen A. The value of the impedance is minimum B. The power factor is zero C. The current leads the total voltage by 90° D. The total voltage is zero

What is the time constant for L of 240 mH in series with R of 20 n? A. 12 ms B. 4.8 s C. 83.3s D. 12 s

. The unit of elastance is A. Farad B. Daraf C. Siemen D. Henry

428. It is the number of complete cycles of alternating voltage or current complete each second A. Period B. Frequency C. Amplitude D. Phase

498. A unit step voltage is applied at t = 0 to a series RL circuit with zero initial conditions A. It is possible for the current to be oscillatory B. The voltage across the resistor at t = 0+ is zero C. The energy stored in the inductor in the steady state is zero D. The resistor current eventually falls to zero

617. EMF has the unit of _________. A. power B. energy C. charge D. none of these

630. The temperature coefficient of resistance of a conductor ________ with rise in temperature. A. increases B. decreases C. remains unchanged D. none of these

711. The hot resistance of a 100 watt, 250 V incandescent lamp would be A. 2.5 ohms B. 625 ohms C. 25 ohms D. none of the above

793. One kWh of energy equals nearly A. 1000 W B. 860 kcal C. 4186 J D. 735.5 W

837. In the circuit shown in Fig. 17.6, the number of nodes is __________. electrical circuit figure 17.6 A. one B. two C. three D. four

889. The Norton equivalent circuit for the network of Fig. 18.6 between A and B is ______ current source with parallel resistance of ______. electrical circuit figure 18.6 A. 2 A, 6 Ω B. 3 A, 2 Ω C. 2 A, 3 Ω D. 3 A, 9 Ω

892. Two 6 V, 2 Ω batteries are connected in series aiding. This combination can be replaced by a single equivalent current generator of ______ with a parallel resistance of ______ ohm. A. 3 A, 4 Ω B. 3 A, 2 Ω C. 3 A, 1 Ω D. 5 A, 2 Ω

Norton's theorem is Thevenin's theorem. A. The same as B. The converse of C. Older that D. More accurate than

Parallel resonant circuit is sometimes called as A. Acceptor circuit B. Rejector circuit C. Inductive circuit D. Capacitive circuit

The second strip of an electronic resistor color-code represents A. The multiplier B. The second digit of the value C. The temperature D. The tolerance

Thevenin's theorem is what form of an equivalent circuit? A. Current B. Voltage C. Both current and voltage D. Neither current nor voltage

347. A chosen closed path of current flow in a network. In making this current path there should be no node nor elements that are passed more than once. A. node B. junction C. mesh D. loop

366. What is the frequency of an alternating current, if it reaches 90° within 4.167 ms? A. 20 Hz B. 30 Hz C. 50 HZ D. 60 Hz

403. If a circuit has an admittance of Y = 0.2 + j0.6, the circuit is A. purely inductive B. inductive C. capacitive D. reactive

405. What is the resonant frequency of a circuit when L is 50 microhenrys and C is 40 picofarads are in parallel? A. 7.96 MHz B. 79.6 MHz C. 3.56 MHz D. 1.78 MHz

618. Potential difference has the unit of _________ . A. charge B. power C. energy D. none of these

802. 1000 kW is equal to how many is ergs/sec. A. 2 x 10^13 B. 1 x 10^16 C. 1 x 10^13 D. 2 x 10^10

822. ECE Board Exam November 1997 Find the Thevenin's impedance equivalent across R2 of a linear close circuit having 10 volts supply in series with the resistors (R1 = 100 ohms and R2 = 200 ohms). A. 6.66 ohms B. 6.666 kohms C. 66.6 ohms D. 666 ohms

831. Three resistors of 6-ohm resistance are connected in delta. Inside the delta another 6-ohm resistors are connected in wye. Find its resistance between any two corners. A. 2 ohms B. 3 ohms C. 4 ohms D. 1 ohm

839. The circuit shown in Fig. 17.6 has __________ branches. electrical circuit figure 17.6 A. two B. four C. three D. none of these

Electric energy refers to A. Volt divided by coulomb B. Volt-ampere C. Volt-coulomb D. Watt divided by time

The reason why electrical appliances are not connected in series. A. Greater electrical power saving B. Power loss is minimum C. Appliances have different current ratings D. All of the above

The superposition theorem is used when the circuit contains A. Reactive elements B. Active elements C. Number of voltage sources D. Single voltage source

The voltage lags the current by n 2 cycle in a A. Purely resistive circuit B. Purely inductive circuit C. Purely capacitive circuit D. Circuit containing resistance, capacitance and inductance

What fusion of elements is without chemical action between them? A. Mixture B. Compound C. Alloy D. Ionization

414. What will happen to a parallel ac-circuit if its line frequency is more than the resonant frequency? A. becomes purely resistive B. becomes purely capacitive C. becomes inductive D. becomes capacitive

417. If an ac-series circuit is supplied with a source whose frequency is less than that of fr, the circuit becomes A. resistive B. reactive C. inductive D. capacitive

686. ECE Board Exam April 1998 When resistors are connected in series, what happens? A. Nothing B. The tolerance is decreased C. The effective resistance is decreased D. The effective resistance is increased

691. ECE Board Exam April 1998 With the same voltage applied which of the following allows more current? A. 25 ohms B. 250 ohms C. 2.5 ohms D. 0.25 ohms

717. Two resistances of 6 ohms and 3 ohms are connected in parallel. The total resistance is ________ A. 9 ohms B. 18 ohms C. 0.5 ohm D. 2 ohms

798. The current in an electric lamp is 5 amperes. What quantity of electricity flows toward the filament in 6 minutes? A. 30 C B. 3600 C C. 72 C D. 1800 C

803. When current flows through heater coil, it glows but supply wiring does not glow because A. supply wiring is covered with insulation wiring B. current through supply line flows at slower speed C. supply wires are made of superior material D. resistance of heater coil is more than that of supply wire

813. EE Board Exam April 1991 Twelve similar wires each of resistance 2 ohms are connected so as to form a cube. Find the resistance between the two corners of the same edge. A. 1.133 ohms B. 1.102 ohms C. 1.125 ohms D. 1.167 ohms

819. EE Board Exam April 1980 Determine I in the figure. electrical circuit figure 17.5 A. 0.028 A B. 0.010 A C. 0.025 A D. 0.014 A

ECE Board Exam April 2000 528. It is defined as anything that occupies space and has weight. A. atom B. compound C. molecule D. matter

Effects of capacitance A. It opposes any change in the amount of voltage B. Voltage is lagged behind the current by a quarter cycle C. Electric energy is stored in the capacitor in the form of electrostatic field D. All of the above

Form its definition, the unit of electric field, { is the N/C and equivalent unit of { is the A. V(m)2 B. V(m) C. V/m2 D. V/m

If two resistances of 9 Q and 6 Q are connected in parallel, the total resistance is A. 54 Q B. 0.3 Q C. 15 Q D. 3.6 Q

The result of rust in electrical (wire) connection is A. Inductance B. Conductance C. Impedance D. Resistance

What determines the magnitude of electric current? A. The rate at which electrons are produced B. The type of material used C. The current carrying capacity of the circuit D. The rate at which electrons pass a given point

316. Five picofarad is equivalent to ________. A. 5 x 10 to the -12th B. 50 x 10 to the -12th C. 5 x 10 to the -10th D. 500 x 10 to the -10th

712. The voltage drop across 14.5 ohm resistor in Fig. 15.1 is __________. electrical circuit figure 15.1 A. 29 V B. 14 V C. 30.5 V D. 18 V

716. When a number of resistances are connected in parallel, the total resistance is _______ A. less than the smaller resistance B. greater than the smaller resistance C. between the smaller and greatest resistance D. none of the above

721. If 18 resistances, each of value 36 ohms, are connected in parallel, then the total resistance is _________ A. 2 ohms B. 54 ohms C. 36 ohms D. none of the above

738. The resistance across terminals 1 and 2 in Fig. 15.12 is _________ electrical circuit figure 15.12 A. 6 ohms B. 12 ohms C. 18 ohms D. 24 ohms

740. Referring to Fig. 15.13, the resistance across terminals BE is ________ electrical circuit figure 15.13 A. 9 ohms B. 18 ohms C. 10 ohms D. none of the above

743. Referring to Fig. 15.13, the power loss in 11 ohms will be ______ electrical circuit figure 15.13 A. 11 W B. 24 W C. 16 W D. none of the above

746. If in Fig. 15.14, both switches S1 and S2 are closed, then ________ electrical circuit figure 15.14 A. L1 will be brighter than L2 or L3 B. L1 will be dimmer than L2 or L3 C. L1 will be as bright as L2 or L3 D. none of the above

748. If in Fig. 15.14 switches S1 and S2 are closed and the supply voltage is increased to 400 V, then ________ electrical circuit figure 15.14 A. lamp L1 will burn out B. lamp L2 will burn out C. both lamps L2 and L3 will burn out D. all the lamps will be safe

750. Whatever the battery voltage in Fig. 15.16, it is certain that smallest current will flow in the resistance of ______ ohm. electrical circuit figure 15.16 A. 300 B. 500 C. 200 D. 100

752. A 100-W, 110-V and a 50-W lamp are connected in series across a 220-V dc source. If the resistances of the two lamps are assumed to remain constant, the voltage across the 100-W lamp is ________ volt. A. 110 B. 73.3 C. 146.7 D. 220

757. With reference to Fig 16.5, which of the following statement is true? electrical circuit figure 16.5 A. E and R1 form a series circuit B. R1 is in series with R3 C. R1 is in series with R2 D. there is no series circuit

A rheostat is a form of A. Variable resistor B. Variable capacitor C. Potentiometer D. Thermocouple

Of the equivalent combination of units, which one is not equal to watt? A. Q2 /V B. AV C. A2 Q D. J/s

The current is times the maximum current at half-power points of a resonance curve. A. 0.707 B. 1.414 C. 0.5 D. 0.632

What is the form factor of a triangular wave? A. 1.16 B. 1.11 C. 1.73 D. 1.41

350. A common connection between circuit elements or conductors from different branches. A. node B. junction C. ground D. mesh

457. A 25 ohm resistor connected in series with a coil of 50 ohm resistance and 150 mH inductance. What is the pf of the circuit? A. 85% B. 80% C. 90% D. 75%

458. A current wave is represented by the equation i = 10 sin 251t. The average and RMS value of current are A. 7.07 A; 6.63A B. 6.36A; 7.07A C. 10A; 7.07A D. 6.36A; 10A

460. An inductive circuit of resistance 16.5 ohms and inductive of 0.14 H takes a current of 25 A. If the frequency is 50 Hz, the supply voltage is A. 117.4 V B. 1174 V C. 1714 V D. 1471 V

461. The current taken by a circuit is 1.2 A when the applied potential difference is 250 V and the power taken is 135 W. The power factor is A. 0.35 B. 0.45 C. 0.55 D. 0.65

719. The current in 2.5 ohm resistor in Fig. 15.4 will be _________ electrical circuit figure 15.4 A. 3 A B. 4.5 A C. 2.5 A D. 2 A

763. Two resistors A and B made of different materials have temperature coefficients of resistance at 20°C of 0.004 and 0.006 respectively. When connected across a voltage source at 20°C, they draw current equally. What percentage of the total current at 100°C does resistor A carry? A. 47.14% B. 52.86% C. 61.34% D. 38.66%

777. REE Board Exam September 2000 What is 1 kW-hr in BTU? A. 4,186 B. 3,413 C. 746 D. 1,000

778. REE Board Exam October 1998 What is the work in ergs needed to raise a 10 g weight 100 m up? A. 4.9 x 10^5 B. 9.8 x 10^7 C. 98 x 10^7 D. 1.96 x 10^7

812. EE Board Exam April 1991 Twelve similar wires each of resistance 2 ohms are connected so as to form a cube. Find the resistance between the two diagonally opposite corners. A. 1.45 ohms B. 1.66 ohms C. 2.01 ohms D. 1.28 ohms

820. ECE Board Exam April 1999 In Kirchhoff's current law, which terminal of a resistance element is assumed to be at a higher potential (more positive) than the other? A. The terminal where the current exits the resistance elements B. The terminal where the current enters the resistance elements C. Either A or B can be arbitrarily selected D. The terminal closest to the node being analyzed

844. To solve the circuit shown in Fig. 17.7 by superposition theorem, we require ________ electrical circuit figure 17.7 A. one circuit B. two circuits C. three circuits D. none of these

846. In the circuit shown in Fig. 17.8, the voltage at node B with D is calculated to be 15 V. The current in the 3 Ω resistor will be electrical circuit figure 17.8 A. 2 A B. 5 A C. 2.5 A D. none of these

849. The superposition theorem is used when the circuit contains A. a single voltage source B. a number of passive source C. passive elements only D. none of these

ECE Board Exam November 2000 562. A resistor which is used to draw a fixed amount of current A. potentiometer B. bleeder resistor C. fixed resistor D. rheostat

ECE Board Exam November 2000 570. Ten micro-microfarads is equivalent to __________. A. 100 picofarads B. 100 nanofarad C. 1000 milli microfarad D. 10.0 picofarads ECE Board Exam November 1995

ECE Board Exam November 2001 535. One of the following is the best conductor of electricity. A. Air B. Copper C. Carbon D. Silicon

In an ac circuit with XL and R in series, the A. Voltages across R and XL are in phase B. Voltage across R lags the voltage across XL by 90° C. Voltages across R and XL are 180° out-of-phase D. Voltage across R leads the voltage across XL by 90°

In an ac circuit with a resistive branch and an inductive branch in parallel, the A. Voltage across the inductance leads the voltage across the resistance by 90° B. Resistive branch current is 90° out of phase with the inductive branch current C. Resistive and inductive branch currents have the same phase D. Resistive and inductive branch currents are 180° out-of-phase

In an ac wave, 30 degrees of phase is of a cycle. A. ½ B. 1/12 C. 1/3 D. 1/30

What capacitance exists not through design but simply because two conducting surfaces are relatively close to each other? A. Surge B. Stray C. Natural D. Normal

418. _________ is a parallel LC circuit. A. Parallel resisting circuit B. Static circuit C. Tank circuit D. Hartley circuit

459. Calculate the susceptance in mho of a circuit consisting of resistor of 10 ohms in series with a conductor of 0.1 H, when the frequency is 50 Hz. A. 0.0303 B. 0.0092 C. -0.029 D. 32.95

464. An impedance draws a current I = 10 cos(wt - 30) from the voltage V = 220sin(wt + 30). What is the impedance? A. 15.6 - j15.6 B. 15.6 + j15.6 C. 19.1- j11.1 D. 11.0 + j19.1

465. The input of an a.c circuit having pf = 0.8 lagging is 20 KVA. The power drawn by the circuit is ________ Kw. A. 12 B. 20 C. 16 D. 8

501. The substation bus bar is made up of 2 inches round copper bars 20 ft long. What is the resistance of each bar if resistivity is 1.724 x 10-6 ohm-cm. A. 7.21 x 10-5 Ω B. 13.8 x 10-6 Ω C. 5.185 x 10-5 Ω D. 2.96 x 10-5 Ω

593. A piece of wire has a resistance of 0.5 ohm. The length is doubled and the area is increased four times. What is its resistance? A. 0.75 ohm B. 0.50 ohm C. 0.25 ohm D. 1 ohm

594. Copper wire of certain length and resistance is drawn out to four times its length without change in volume. What is the resistance of the bar? A. unchanged B. R/16 C. 16R D. 4R

601. A certain wire 20 ft long and 100 circular mil area has a resistance of 1.6 Ω. What is its resistivity? A. 10.3 ohm-CM/ft B. 2.2 ohm-CM/ft C. 8 ohm-CM/ft D. 15.2 ohm-CM/ft

626. The resistance of a material 2 m long and 2 m^2 in cross-sectional area is 1.6 x 10^-8 Ω. Its specific resistance will be __________. A. 3.2 x 10^-8 ohm-m B. 6.4 x 10^-8 ohm-m C. 1.6 x 10^-8 ohm-m D. 0.16 x 10^-8 ohm-m

631. Insulators have _________ temperature coefficient of resistance. A. zero B. positive C. negative D. none of these

714. Referring to Fig. 15.2, the total circuit resistance will be _________ electrical circuit figure 15.2 A. 1000 ohms B. 400 ohms C. 1400 ohms D. 135 ohms

718. The value of R that will give a total resistance of 1.5 ohms in Fig. 15.3 is ____ electrical circuit figure 15.3 A. 4 ohms B. 6 ohms C. 3 ohms D. 9 ohms

723. The resistance across the terminals AB of the circuit shown in Fig. 15.5 is ________ electrical circuit figure 15.5 A. 36 ohms B. 18 ohms C. 9 ohms D. 15 ohms

A real current source has A. Infinite internal resistance B. Zero internal resistance C. Large internal resistance D. Small internal resistance

A switch designed to have low capacitance between its terminal when open. A. LOCAP switch B. AntiLOCAP switch C. Anticapacitance switch D. Capacitance switch

A three-by-three, series-parallel matrix of resistors, all having the same ohmic value, would have a net resistance of A. One-third the value of a single resistor B. Three times the value of a single resistor C. The same value as a single resistor D. Nine times the value of a single resistor

If a capacitor is rated for 200V dc, what is its effective ac working voltage? A. 50 V B. 100 V C. 200 V D. 400 V

Inductive reactance applies only to sine waves because it A. Increases with lower frequencies B. Increases with lower inductance C. Depends on the factor 2 1t D. Decreases with higher frequencies

REE Board Exam September 2003 520. In cgs system, what is the unit of emf where I is in abampere and P is in erg per second? A. millivolt B. kilovolt C. abvolt D. volt

Refers to the outward-curving distortion of the lines of force near the edges of two parallel metal plates that form a capacitor. A. Skin effect B. Night effect C. Edge effect D. Hall effect

The distance between the capacitor plates increases two times, then its capacitance A. Increases two times B. Increases four times C. Decreases two times D. Decreases four times

What is the reciprocal of quality factor? A. Power factor B. Reactive factor C. Dissipation factor D. 1/Q factor

What is the resonant frequency of a circuit when L of 3 microhenrys and C of 40 picofarads are in series? A. 14.5 kHz B. 145 MHz C. 14.5 MHz D. 145 kHz

What is the specific resistance of a pure silicon? A. 55 n-mm B. 55 n-m C. 55 n-cm D. 55 kn-m

What is the temperature coefficient of the resistance Eureka? A. Infinity B. Negative C. Almost zero D. Positive

348. A set of circuit elements that forms a closed path in a network over which signal can circulate. A. node B. junction C. mesh D. loop

402. What is the power factor of a circuit if the inductive susceptance and conductance have the same value? A. 0.325 B. 0.525 C. 0.673 D. 0.707

447. The AC system is preferred over DC system because A. Ac voltages can easily changed in magnitude B. Dc motors do not have fine speed control C. High voltage AC transmission is less efficient D. DC voltage cannot be used for domestic appliances

455. Determine the power angle in the series circuit which consists of R = 25 ohms, L = 0.2 H across a power supply of 200 V, 30 Hz. A. 36.4 degrees B. 52.4 degrees C. 46.4 degrees D. 56.4 degrees

463. The form factor of half wave rectified signal is equal to _________. A. 1.11 B. 0.786 C. 2.22 D. 1.57

466. A capacitor connected to a 115 V, 25 Hz supply takes 5 A. What current will it take when the capacitance and frequency are doubled? A. 2 A B. 5 S C. 10 A D. 20 A

644. Which of the following material has a negative temperature coefficient of resistance? A. brass B. copper C. aluminum D. carbon

648. A coil has a resistance of 100 ohms at 90°C. At 100°C, its resistance is 101 ohms. What is the temperature coefficient of the wire at 90°C? A. 0.01 B. 0.1 C. 0.0001 D. 0.001

649. What is the unit for charge (Q)? A. Farad B. Joule C. Siemens D. Coulomb

653. REE Board Exam March 1998 Three resistors of 10, 15 and 20 ohms each are connected in parallel. What is the equivalent resistance? A. 45 ohms B. 17.2 ohms C. 0.22 ohm D. 4.62 ohms

662. REE Board Exam April 1997 A circuit consists of three resistors rated 3-Ω, 4-Ω and 5-Ω connected in parallel. If the circuit is connected to a battery which has an internal resistance of 0.2-Ω, what would be the current through the 4-Ω resistor? A. 2.04 A B. 4.8 A C. 2.4 A D. 3.0 A

672. ECE Board Exam March 1996 When you increase the resistance in a circuit, the flow of electrons will __________. A. be constant B. flow faster C. be stopped D. be decreased

673. ECE Board Exam April 2001 Which of the following allows more current if applied to the same voltage? A. 0.002 siemen B. 25 ohms C. 0.004 siemen D. 2.5 ohms

871. If in Fig. 18.4, the value of RL = 6 Ω, then current through RL is _______. electrical circuit figure 18.4 A. 2 A B. 1.5 A C. 1.75 A D. 1 A

876. Kirchhoff's voltage law is concerned with A. IR drops B. battery e.m.f.s. C. junction voltages D. both A and B

880. Point out the WRONG statement. In the node-voltage technique of solving networks, choice of a reference node does not A. affect the operation of the circuit B. change the voltage across any element C. alter the p.d. between any pair of nodes D. affect the voltages of various nodes

881. The nodal analysis is primarily based on the application of A. KVL B. KCL C. Ohm's Law D. both B and C

890. The Norton equivalent of a circuit consists of a 2 A current source in parallel with a 4 Ω resistor. Thevenin equivalent of this circuit is a ____ volt source in series with a 4 Ω resistor. A. 2 ohms B. 0.5 ohms C. 6 ohms D. 8 ohms

ECE Board Exam April 2000 547. A substance which cannot be reduced to a simpler substance by chemical means A. atom B. molecule C. matter D. element

ECE Board Exam April 2000 569. What does the fourth loop of an electronic resistor color code represent? A. Multiplier B. Temperature C. First digit of the equivalent value D. Tolerance

ECE Board Exam April 2001 541. The term describes a material whose resistance remains relatively constant with changes in temperature. A. positive temperature coefficient B. negative temperature coefficient C. neutral temperature coefficient D. zero temperature coefficient

Which of the following elements is active? A. Resistor B. Inductor C. Capacitor D. Ideal voltage source

. "Any resistance R in a branch of a network in which a current I is flowing can be replaced by a voltage equal to IR". This states A. Compensation theorem B. Reciprocity theorem C. Millman's theorem D. Superposition theorem

. In a resonant circuit, if Q 2: 10 resonant frequency bandwidth. A. Bisects B. Exceeds C. Is less than D. Is equal to

. The voltage cannot be exactly in phase with the current in a circuit that contains A. Only capacitance B. Only resistance C. Inductance and capacitance D. Inductance, capacitance and resistance

374. In an ac-circuit, if the voltage and current are in phase, the circuit is A. resistive B. reactive C. capacitive D. inductive

378. A resistive and a capacitive load of equal magnitude is connected in series, determine the phase difference between the voltage and the current. A. current leads the voltage by 45° B. current lags the voltage by 45° C. current leads the voltage by 90° D. current lags the voltage by 90°

Leakage resistance in a capacitor results into A. Internal heating B. Internal bleeding C. Shorter useful life D. Short-circuiting

Permeability is otherwise known as A. Magnetic conductivity B. Magnetic susceptibility C. Electric conductivity D. Electric susceptibility

A series RLC circuit consists of a 10 Q resistor in series with L = 10 µH, and C = 100 µF. Determine a new value of I, for which the resonant frequency is one -half the original value. A. 40 µH B. 40 mH C. 40 pH D. 40 nH

An alloy composed of 84 % copper, 12 % manganese and 4 % nickel. A. Manganin B. Constantan C. Nichrome D. German silver wire

An intermittent and non-symmetrical alternating current like that obtained from the secondary winding of an induction coil A. Faradic current B. Transient ac current C. Inductive current D. Capacitive current

At what frequency will an inductor of 5mH have the same reactance as a capacitor of 0.1 µF? A. 7.12 kHz B. 7.12 Hz C. 7.12MHz D. 7.12 GHz

At what frequency will the current in a series RLC circuit reach its maximum value for an applied voltage of 15 V with R = 500 n, L = 100 µH and C = 0.001 µF? A. 503 kHz B. 403 kHz C. 603 kHz D. 303 kHz

The internal resistance of an ideal current source is A. Infinite B. Zero C. Equal to the load resistance D. To be determined

Which of the following conditions is not true for a series RLC circuit at resonance? A. Z = jXL B. XL = XC C. The power factor is one D. The magnitude of Z is -/R2 + (XL - XC )2

. Which one of the following elements serves as a protection against overload? A. Fuse B. Switch C. Resistor D. Relay

3. Which of the following is the most popular waveform? A. Sinusoidal B. Square wave C. Triangular D. Sawtooth

Two complex numbers or phasors are said to be conjugate if they A. Differ only in the algebraic sign of their quadratic components B. Differ only in the algebraic sign of their real components C. Are equal in their real and quadrature components including algebraic signs D. Are equal in their real components but differ in their quadrature components including algebraic signs.

And ideal current source has an internal conductance of -----siemen(s) A. Infinite B. One C. Zero D. One million

As applied to a series RLC circuit, bandwidth means A. The frequency range for maximum power transfer B. The difference between the highest and lowest frequencies of the oscillator C. The separation of the half-power points D. The frequency at which XL = XC

In an ac circuit with inductive reactance, the A. Phase angle of the circuit is always 45° B. Voltage across the inductance must be 90° out-of-phase with the applied voltage C. Current through the inductance lags its induced voltage by 90° D. Current through the inductance and voltage across it are180° out-of-phase

. If two equal resistances connected in series across a certain supply are now connected in parallel across the same supply, the power produced will be that of series connection A. One-half B. One-fourth C. Two times D. Four times

What determines the direction of induced emf in a conductor or coil? A. Cork screw rule B. Fleming's left hand rule C. Ampere's circuital law D. Fleming's right hand rule

What is the other name of relative permittivity? A. Dielectric strength B. Potential gradient C. Breakdown voltage D. Specific inductance capacity

. An ac series circuit is composed of a resistance of 20 n, inductive reactance of 40 n, and a capacitive reactance of 15 n. If a current of 1 ampere is flowing, what is the applied voltage A. 320 V B. 32 V C. 220 V D. 22 V

. An open inductor has A. Zero resistance and infinite inductance B. Infinite resistance and zero inductance C. Infinite resistance and infinite inductance D. Zero resistance and zero inductance

In liquids and gases, ionization current results from a flow of A. Positive or negative ions B. Free electrons C. Ions that are lighter in weight than electrons D. Protons

The charge in the capacitor is stored at the A. Terminals B. Plates C. Dielectric D. Air

The ohmic value of a resistor with negative temperature coefficient A. Increases with increasing temperature B. Increase with decreasing temperature C. Stays unchanged with temperature change D. Stays unaffected even with increasing temperature

The reason why electrical appliances are connected in parallel. A. It is a simple circuit B. This makes the operation of appliances independent with each other C. This results in reduced power consumption D. All of the above

The symbol Q refers to A. Resonance quotient B. Quality factor C. Power quotient D. Qualification test

751. Which of the following statement is TRUE both for a series and parallel DC circuit? A. powers are additive B. voltages are additive C. current additive D. elements have individual currents

764. A conductor has a resistance of 7 ohms at 0C. At 20°C, the resistance has become 7.5 ohms. Calculate the temperature coefficient of the conductor at 20°C. A. 1/300 /°C B. 1/400 /°C C. 1/500 /°C D. 1/600 /°C

766. EE Board Exam April 1992 An electric kettle was marked 500 W, 230 V found to take 15 minutes to bring 1 kilogram of water at 15°C to boiling point. Determine the heat efficiency of the kettle. A. 79.1% B. 75.3% C. 72.4% D. 74.8%

768. EE October 1989 A total of 0.8 kg of water at 20°C is placed in a 1-kW electric kettle. How long a time in minute is needed to raise the temperature of the water to 100°C? A. 4.46 min B. 5.32 min C. 5.34 min D. 4.56 min

775. REE Board Exam September 2001 How many joules per second are then in 10 watts? A. 10 B. 5 C. 20 D. 24.5

788. The SI unit of energy is A. Joule B. kWh C. kcal D. m-kg

791. For a given line voltage, four heating coils will produce maximum heat when connected A. all in parallel B. all in series C. with two parallel pairs in series D. one pair in parallel with the other two in series

795. A 100 W light bulb burns on an average of 10 hours a day for one week. The weekly consumption of energy will be ______________ unit/s. A. 7 B. 70 C. 0.7 D. 0.07

799. An electric heater is rated at 120 volts, 1000 watts and is used to boil water. Calculate the time in minutes to raise the temperature of 1 liter of water from 15°C to boiling. The heater has an over-all efficiency of 92%. A. 6.4 minutes B. 5.4 minutes C. 4.4 minutes D. 3.4 minutes

807. EE Board Exam October 1986 An LRT car, 5 km distance from the Tayuman station, takes 100 A over a 100 mm hard drawn copper trolley wire having a resistance of 0.270 ohm per km. The rail and ground return has a resistance of 0.06 ohm per km. If the station voltage is 750 V, what is the voltage of the car? A. 585 V B. 590 V C. 595 V D. 580 V

824. ECE Board Exam November 1998 If a resistance element is part of two loops, how many voltage drops must be calculated for that component? A. Two B. Three C. One D. None

616. EMF in a circuit is _________. A. cause current to flow B. maintains potential difference C. increases the circuit resistance D. none of these

690. ECE Board Exam November 2000 A device that draws current A. Source B. No load C. Load D. Shunt

700. A variable resistor R is connected in parallel with a fixed resistor of 1.25 ohms. The combination is then connected across a 12 V battery with internal resistance of 0.25 Ω. Solve for the maximum power that can delivered to R. A. 130.20 W B. 115.52 W C. 120.21 W D. 142.42 W

595. Current is simply _________. A. Flow of electrons B. Flow of protons C. Radiation D. Emission

446. The reciprocal of capacitance is called A. Conductance B. Elastance C. Permitivity D. permeability

.The ratio between the active power and the apparent power of a load in an ac circuit is called A. Quality factor B. Power factor C. Power ratio D. Power reactive

. Resistor with colored bands in the body A. Wire-wound resistor B. Carbon-composition resistor C. Potentiometer D. Rheostat

What can be used to estimate resonant frequency and to find reactance at any frequency for any value of capacitor or inductor? A. Smith chart B. Reactance chart C. Impedance chart D. Resonance chart

369. What is the average voltage of an alternating voltage, v = 100sin120πt? A. 31.8 V B. 63.6 V C. 70.71 V D. 0 (zero) V

2. [ELEX]

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