correl 1

92. A time is zero during a current growth in an inductance circuit of current rise is 300 amp/sec when 120V is suddenly applied. What is the inductance of the circuit? A. 0.04 H B. 0.4 H (120/ 300) C. 4 mH D. 4 H

0.4 H

67. Relative permeability of vacuum is: A. 4π x 10-7 H/m B. 1 H/m C. 1 D. ¼ π

1

39. When the output voltage level of a filter decreases by -3dB, its absolute value changes by a factor of: A. 20.5 B. 1 / 20.5 C. 2 D. ½

1 / 20.5

86. When output voltage level of a filter decreases by -3 dB, its absolute value changes by a factor of: A. 20.5 B. 1 / 20.5 C. 2 D. ½

1 / 20.5

18. The electric energy required to raise the temperature of a given amount of water is 1,000 kWh. If heat losses are 25%, the total heating energy required is _____ kWh. A. 1,500 B. 1,250 C. 1,333 D. 1,000

1,250

20. Work equal to 136.0 joules is expended in moving 8.5x1010 electrons between two points in an electric circuit. What potential difference does this establish between the two points? A. 50 V B. 80 V C. 100 V D. 120 V

100 V

73. A 25.0 Ω resistance has a voltage v=150sin(377)t(V). Find the average power pavg over one cycle. A. 450 W P=(0.5)(150)(150/25) B. 400 W C. 500 W D. 430 W

450 W

12. The reactance offered by a capacitor to alternating current of frequency 50 Hz is 10 ohms. If frequency is increased to 100 Hz, reactance becomes _____ ohm. A. 20 B. 5 C. 2.5 D. 40

5

5. The amplifier with the conduction angle for the transistor is significantly less than 180 degrees: A. Class A B. Class B C. Class C D. Class D

6. The measure of electric charge stored in this element is called A. Resistance B. Inductance C. Susceptance D. Capacitance E. Capacitance

27. In a low-pass filter, the cutoff frequency is represented by the point where the output voltage is reduced to _____ percent of the input voltage A. 50 B. 70.7 C. 63.2 D. 33.3

70.7

71. In a low-pass filter, the cutoff frequency is represented by the point where the output voltage is reduced to _____ percent of the input voltage. A. 50 B. 70.7 C. 63.2 D. 33.3

70.7

23. The force applied to an object moving in the x direction varies according to F = 12 / x2 (N). Find the work done in the interval 1m ≤ x ≤ 3m. A. 8 J B. 10 J C. 12 J D. 24 J

8 J

52. An opto-isolator consists of: A. Two Zener diodes back-to-back B. A LED and a photodiode C. Two NPN transistor in series D. A PNP transistor followed by NPN transistor

A LED and a photodiode

55. Transconductance is a ratio of: A. A change in drain voltage to a change in source voltage B. A change in gate current to a change in source voltage C. A change in drain current to a change in gate voltage D. A change in gate current to a change in drain voltage

A change in drain current to a change in gate voltage

58. The bipolar transistors or JFETs in a multivibrator are usually connected in: A. Class B B. A common-emitter or common-source arrangement C. Class C D. A common-collector or common-drain arrangement

A common-emitter or common-source arrangement

45. Which of the IC is used to determine whether the voltage levels are the same or not? A. An op-amp B. A timer C. A comparator D. A multiplexer/demultiplexer

A comparator

9. Electromagnet used to generate a magnetic field in an electro-magnetic machine, typically a rotating electrical machine A. A solenoid B. A commutator C. An armature coil D. A field coil

A field coil

29. A common-base circuit is commonly employed as: A. A microwave oscillator B. A low-pass filter C. A radio-frequency power amplifier D. A noise generator

A radio-frequency power amplifier

62. 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

All in parallel

53. The active materials of a nickel-iron battery are: A. Nickel hydroxide B. Powdered iron and its oxides C. 21% solution of caustic potash D. All of the above

All of the above

54. Electrical energy is converted to heat at the rate of 1kJ/min is a resistor which has 280C/min passing through. What is the voltage difference across the resistor terminals? A. 3.8 V B. 3.6 V C. 0.3 V D. 280 Kv

All of the above

69. Active materials of a lead-acid cell are: A. Lead peroxide B. Sponge lead C. Dilute sulfuric acid D. All of the above

All of the above

78. The moving system of an indicating type of electrical instrument is subjected to: A. A deflecting torque B. A controlling torque C. A damping torque D. All of the above

All of the above

36. It is basically a non-linear switching amplifier. A. Class A B. Class B C. Class C D. Class D 37. The ratio of Ah efficiency to Wh efficiency of a lead-acid cell is: A. Always less than one B. Just one C. Always greater than one D. Either A or B

Always greater than one

10. Moving iron instruments can be used for measuring: A. Direct currents and voltages B. Alternating currents and voltages C. Radio frequency currents D. Both A and B

Both A and B

94. In small dc machines, armature slots are sometimes not made axial but are skewed. Though skewing makes winding a little more difficult, yet it results in: A. Quieter operation B. Slight decrease in losses C. Saving of copper D. Both A and B

Both A and B

21. Permanent-magnet moving-coil ammeter have uniform scales because: A. Of eddy current damping B. They are spring-controlled C. Their deflecting torque varies directly as current * D. Both B and C

Both B and C

70. The unit of electric intensity is: A. Joule/coulomb B. Newton/coulomb C. Volt/meter D. Both B and C

Both B and C

74. As compared to constant-current system, the constant-voltage system of charging a lead-acid cell has the advantage of: A. Avoiding excessive gassing B. Reducing time of charging C. Increasing cell capacity D. Both B and C

Both B and C

77. It can create distortion at the zero-crossing point of the waveform due to the transistors dead band of input base voltages. A. Class A B. Class B C. Class C D. Class D

Class B

43. Which of the following circuit generally has the greatest gain? A. Common source B. Common gate C. Common drain D. It depends only on bias, not on which electrode is grounded

Common source

65. A capacitor consists of two: A. Insulation separated by dielectric B. Conductors separated by dielectric C. Ceramic plates and one mica disc D. Silver-coated insulators

Conductors separated by dielectric

72. The commercial efficiency of a shunt generator is maximum when its variable loss equals _____ loss. A. Constant B. Stray C. Iron D. Friction and windage

Constant

91. The sole purpose of a commutator in a dc generator is to: A. Increase output voltage B. Reduce sparking of brushes C. Provide smoother output D. Convert the induced ac into dc

Convert the induced ac into dc

4. The meter movement in an illumination meter measures A. Current B. Voltage C. Power D. Energy

Current

87. The frequency corresponding to half-power point on the response curve of a filter is known as _____. A. Cutoff B. Upper C. Lower D. Roll-off

Cutoff

89. The frequency corresponding to half-power point on the response curve of a filter is known as _____. A. Cutoff B. Upper C. Lower D. Roll-off

Cutoff

14. A gigabyte is a unit commonly used as a measure of A. Data access time B. Data transfer speed C. Data storage capacity D. Data communications accuracy

Data storage capacity

85. The most useful ac bridge for comparing capacitances of two air capacitances is _____ bridge. A. Shering B. De Sauty C. Wien series D. Wien parallel

De Sauty

81. If load on a dc shunt motor is increased, its speed is decreased due primarily to: A. Increase in its flux B. Decrease in back emf C. Increase in armature current D. Increase in brush drop

Decrease in back emf

1. The different sound of the musical instrumentations primarily the result of A. Differences in frequency B. Differences in amplitude C. Differences in wave shape D. Differences in phase

Differences in wave shape

68. Which is the wrong statement? The magnetizing force at the center of a circular coil varies. A. Directly as the number of its turns B. Directly as the current C. Directly as its radius D. Inversely as its radius

Directly as its radius

80. The most efficient form of damping employed in electrical instrument is: A. Air friction B. Fluid friction C. Eddy current D. None of the above

Eddy current

22. Which of the following is zero inside a charged conducting sphere? A. Potential B. Electric intensity C. Both A and B D. Both B and C

Electric intensity

32. The charging of a capacitor through a resistance follows _____. A. Linear law B. Square law C. Exponential law D. Kirchoff's law

Exponential law

63. The unit of absolute permittivity of a medium is: A. Joule/coulomb B. Newton-meter C. Farad/meter D. Farad/coulomb

Farad/meter

95. The critical resistance of the dc generator is the resistance of: A. Armature B. Field C. Load D. Brushes

Field

84. Maxwell's L/C bridge is so called because: A. It employs L and C in two arms B. Ratio L/C remains constant C. For balance, it uses two opposite impedances in opposite arms D. Balance as obtained when L=C

For balance, it uses two opposite impedances in opposite arms

34. Peak values are always: A. Greater than or equal to average values B. Less than average values C. Less than or equal to average values D. Fluctuating

Greater than or equal to average values

51. The current consists mainly of holes when a JFET: A. Has a P-type channel B. Is forward-biased C. Is reversed-biased D. Is zero-biased

Has a P-type channel

64. In practice, Earth is chosen in a place of zero electric potential because it: A. Is non-conducting B. Is easily available C. Keeps losing and gaining electric charge every day D. Has almost constant potential

Has almost constant potential

49. The major advantage of Silicon-on-Insulator are the following except: A. Nominals threshold voltage must be very high B. High diffusion capacitance C. Lower diffusion capacitance D. Lower dynamic power consumption

High diffusion capacitance

59. An IGBT is generally used in: A. High-voltage application B. RF application C. Low-power application D. Low-current application

High-voltage application

31. As compared to a lead-acid cell, the efficiency of a nickel-iron cell is less due to its: A. Lower emf B. Smaller quantity of electrolyte used C. Higher internal resistance D. Compactness

Higher internal resistance

2. Sulphation in a lead-acid battery occur due to A. Trickle charging B. Incomplete charging C. Heavy discharging D. Fast charging

Incomplete charging

83. Maxwell-Wien Bridge is used for measuring _____. A. Capacitance B. Dielectric loss C. Inductance D. Phase angle

Inductance

16. Which device can be used to increase voltage from a source of direct current? A. Induction coil B. Generator C. Electroscope D. Mass spectrometer

Induction coil

25. The efficiency of the generator: A. Depends on the driving power source B. Is equal to the output power divided by driving power C. Is equal to driving voltage divided output voltage D. Is equal to driving current divided output current

Is equal to the output power divided by driving power

38. A varactor diode A. Is mechanically flexible B. Has high power output C. Can produce different waveforms D. Is good for use in frequency synthesizer

Is good for use in frequency synthesizer

26. To measure power-supply voltage being used by the circuit, the voltmeter: A. Is placed in series with the circuit that work from the supply B. Is placed between the negative pole of the supply and the circuit working from the supply C. Is placed between the positive pole of the supply and the circuit working from the supply D. Is placed in parallel with the circuit that works from the supply

Is placed in parallel with the circuit that works from the supply

48. A disadvantage of a MOS component is that: A. It is easily damaged by static electricity B. It needs a high input voltage C. It draws a large amount of current D. It produces a great deal of electrical noise

It is easily damaged by static electricity

47. During the charging of a lead-acid cell: A. Its cathode becomes dark chocolate brown in color B. Its voltage increases C. It gives out energy D. Specific gravity of H2SO4

Its voltage increases

93. The series field of a short-shut dc generator is excited by _____ currents. A. Shunt B. Armature C. Load D. External

Load

19. If X and Y are both high, what is the state of X NAND Y? A. Not enough information B. Low C. High D. This logic statement makes no sense

Low

46. Once a Diac is conducting, the only way to turn it off is with: A. A negative gate voltage B. Breakover C. A positive gate voltage, low-current dropout D. Low-current dropout

Low-current dropout

82. A unit of overall magnetic field quantity is the: A. Maxwell B. Gauss C. Tesla D. Ampere-turn

Maxwell

33. What bridge is used for measuring an unknown inductance in terms of a known capacitance and resistance? A. Maxwell's L/C B. Hay's C. Owen D. Anderson

Maxwell's L/C

42. The bandwidth of an amplifier may be increased by: A. Decreasing the capacitance of it bypass capacitors B. Minimizing its stray capacitances C. Increasing input signal frequency D. Cancelling it

Minimizing its stray capacitances

17. The damping force act on the moving system of an indicating instrument only when it is: A. Moving B. Stationary C. Near its full deflection D. Just starting to move

Moving

61. Shifting the phase of the ac sine wave by 90 degrees is the same thing as: A. Moving it to the right or left by a full cycle B. Moving it to the right or left by 180 C. Moving it to the right or left by a ¼ cycle D. Turning it upside-down

Moving it to the right or left by a ¼ cycle

30. The meter that is suitable for only direct current measurements is: A. Moving-iron type B. Permanent-magnet type C. Electrodynamic type D. Hot-wire type

Moving-iron type

90. An audio oscillator that uses two amplifiers is cascaded, with positive feedback from the output of second stage to the first stage, is known as a: A. Colpitts circuit B. Hartly circuit C. Clap circuit D. Multivibrator

Multivibrator

7. Which of the following is not a basic element of a transformer? A. Core B. Primary winding C. Secondary winding D. Mutual flux

Mutual flux

60. If a 220V heater is used on 110V supply, heat produced by it will be _____ as much. A. One-half B. Twice C. One-fourth D. Four times

One-fourth

66. The capacitance of a capacitor is not influenced by: A. Plate thickness B. Plate area C. Plate separation D. Nature of the dielectric

Plate thickness

50. Inside a conducting sphere, _____ remains constant. A. Electric flux B. Electric intensity C. Charge D. Potential

Potential

76. The kWh meter can be classified as a/an _____ instrument. A. Deflecting B. Digital C. Recording D. Indicating

Recording

35. Heaviside-Campbell Equal Ratio bridge is used for measuring _____. A. Self-inductance in terms of mutual inductance B. Capacitance in terms of inductance C. Dielectric loss of an imperfect capacitor D. Phase angle of a coil

Self-inductance in terms of mutual inductance

56. Data sent along a single line, one bit after another, is called: A. Serial B. Asynchronous C. Synchronous D. Parallel

Serial

44. The extent to which an oscillator maintains a constant frequency is called: A. Sensitivity B. Stability C. Drift ratio D. Gala

Stability

13. The value that a circuit has attained after it has long been switched is called A. Steady state value B. Transient value C. Time constant value D. Leakage value

Steady state value

79. The minimum input current that can be used as a ? is called the: A. Switching current B. Breakdown current C. Low-current dropout current D. Holding current

Switching current

40. The configuration most often used for matching a high input impedance to a low output impedance puts signal ground at: A. The emitter B. The base C. The collector D. Any point; it doesn't matter

The collector

24. The inductance of a coil can be continuously varied by varying: A. The frequency B. The net core permeability C. The wavelength D. The voltage across the coil

The net core permeability

57. In positive-edge is triggering, the change of state occurs when: A. The pulse level is high B. The pulse level is going from high to low C. The pulse level is going from low to high D. The pulse level is low

The pulse level is going from low to high

41. If X is high and Y is low, what is the state of X NOT Y? A. Not enough information B. Low C. High D. This logic statement makes no sense

This logic statement makes no sense

88. In aMOS transistor, which operation is for cut-off mode? A. Vgs > Vt, Vgs < Vgd, and Vds > Vgs - Vt B. Vgs > Vt, Vgd = Vgs, and Vds = 0 C. Vgs > Vt, Vgs > Vgd > Vt, and 0 < Vds < Vgs - Vt D. Vgs < Vt

Vgs < Vt

75. During charging and discharging of a nickel-iron cell: A. Its emf remains constant B. Water is neither formed nor absorbed C. Corrosive fumes are produced D. Nickel hydroxide remains unsplit

Water is neither formed nor absorbed

15. If in the case of a certain dc armature, the number of commutator segments is found either one less or more than the number of slots, the armature must be having a simplex _____ winding. A. Wave B. Lap C. Frog leg D. Multielement

Wave

28. Supposed a certain current in a galvanometer causes the needle to deflect 20 degrees, then the current is doubled. The needle deflection: A. Will reverse direction B. Will decrease C. Will stay the same D. Will increase

Will increase

3. A three-terminal monolithic IC regulator can be used as A. an adjustable output voltage regulator alone B. an adjustable output voltage regulator and a current regulator C. a current regulator and a power switch D. a current regulator alone

an adjustable output voltage regulator alone

11. Lap winding is suitable for _____ current, _____ voltage dc generators A. high, low B. low, high C. low, low D. high, high

high, low

8. Relative permeability equation is A. μ¬r = μ / μ¬0 B. μ¬r = μ x μ¬0 C. μ¬r = μ¬0 / μ D. μ¬r = magnetic susceptibility - 1

μ¬r = μ / μ¬0