FCC Element 3 Part 1/3

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3-9B4 If a 100-ohm resistor is connected across 200 volts, what is the current through the resistor? A. 2 amperes. B. 1 ampere. C. 300 amperes. D. 20,000 amperes.

A. 2 amperes.

3-15B4 What is the time constant of a circuit having a 220-microfarad capacitor and a 1-megohm resistor in parallel? A. 220 seconds. B. 22 seconds. C. 2.2 seconds. D. 0.22 seconds.

A. 220 seconds.

3-15B6 What is the time constant of a circuit having two 220-microfarad capacitors and two 1-megohm resistors all in series? A. 220 seconds. B. 55 seconds. C. 110 seconds. D. 440 seconds.

A. 220 seconds.

3-9B1 What value of series resistor would be needed to obtain a full scale deflection on a 50 microamp DC meter with an applied voltage of 200 volts DC? A. 4 megohms. B. 2 megohms. C. 400 kilohms. D. 200 kilohms.

A. 4 megohms.

3-16B3 In rectangular coordinates, what is the impedance of a network composed of a 10-microhenry inductor in series with a 40-ohm resistor, at 500 MHz? A. 40 +j31400 B. 40 -j31400 C. 31400 +j40 D. 31400 -j40

A. 40 +j31400

3-11B1 What is the most the actual transmit frequency could differ from a reading of 462,100,000 Hertz on a frequency counter with a time base accuracy of ± 0.1 ppm? A. 46.21 Hz. B. 0.1 MHz. C. 462.1 Hz. D. 0.2 MHz.

A. 46.21 Hz.

3-17B4 In polar coordinates, what is the impedance of a network composed of a 300-ohm-reactance capacitor, a 600-ohm-reactance inductor, and a 400-ohm resistor, all connected in series? A. 500 ohms, /37 degrees B. 400 ohms, /27 degrees C. 300 ohms, /17 degrees D. 200 ohms, /10 degrees

A. 500 ohms, /37 degrees

3-11B3 What is the second harmonic of SSB frequency 4146 kHz? A. 8292 kHz. B. 4.146 MHz. C. 2073 kHz. D. 12438 kHz.

A. 8292 kHz.

3-5A6 How does the input impedance of a field-effect transistor compare with that of a bipolar transistor? A. An FET has high input impedance; a bipolar transistor has low input impedance. B. One cannot compare input impedance without first knowing the supply voltage. C. An FET has low input impedance; a bipolar transistor has high input impedance. D. The input impedance of FETs and bipolar transistors is the same.

A. An FET has high input impedance; a bipolar transistor has low input impedance.

The product of the readings of an AC voltmeter and AC ammeter is called: A. Apparent power. B. True power. C. Power factor. D. Current power.

A. Apparent power

3-15B2 What is the time constant of a circuit having two 100-microfarad capacitors and two 470-kilohm resistors all in series? A. 470 seconds. B. 47 seconds. C. 4.7 seconds. D. 0.47 seconds.

B. 47 seconds.

3-15B5 What is the time constant of a circuit having two 100-microfarad capacitors and two 470-kilohm resistors all in parallel? A. 470 seconds. B. 47 seconds. C. 4.7 seconds. D. 0.47 seconds.

B. 47 seconds.

3-11B2 The second harmonic of a 380 kHz frequency is: A. 2 MHz. B. 760 kHz. C. 190 kHz. D. 144.4 GHz.

B. 760 kHz.

3-4A1 What formula would calculate the total inductance of inductors in series? A. LT = L1 / L2 B. LT = L1 + L2 C. LT = 1 / L1 + L2 D. LT = 1 / L1 x L2

B. LT = L1 + L2

3-3A6 Which of these will be most useful for insulation at UHF frequencies? A. Rubber. B. Mica. C. Wax impregnated paper. D. Lead.

B. Mica.

3-5A5 A common emitter amplifier has: A. Lower input impedance than a common base. B. More voltage gain than a common collector. C. Less current gain than a common base. D. Less voltage gain than a common collector.

B. More voltage gain than a common collector.

3-14B1 What is the term for the time required for the capacitor in an RC circuit to be charged to 63.2% of the supply voltage? A. An exponential rate of one. B. One time constant. C. One exponential period. D. A time factor of one.

B. One time constant.

3-14B3 What is the term for the time required for the current in an RL circuit to build up to 63.2% of the maximum value? A. One time constant. B. An exponential period of one. C. A time factor of one. D. One exponential rate.

A. One time constant.

3-6A4 What is the easiest voltage amplitude to measure by viewing a pure sine wave signal on an oscilloscope? A. Peak-to-peak. B. RMS. C. Average. D. DC.

A. Peak-to-peak.

3-9B6 A relay coil has 500 ohms resistance, and operates on 125 mA. What value of resistance should be connected in series with it to operate from 110 V DC? A. 150 ohms. B. 220 ohms. C. 380 ohms. D. 470 ohms.

C. 380 ohms.

3-15B3 What is the time constant of a circuit having a 100-microfarad capacitor and a 470-kilohm resistor in series? A. 4700 seconds. B. 470 seconds. C. 47 seconds. D. 0.47 seconds.

C. 47 seconds.

3-4A6 How might you reduce the inductance of an antenna coil? A. Add additional turns. B. Add more core permeability. C. Reduce the number of turns. D. Compress the coil turns.

C. Reduce the number of turns.

3-8A1 What is the term used to identify an AC voltage that would cause the same heating in a resistor as a corresponding value of DC voltage? A. Cosine voltage. B. Power factor. C. Root mean square (RMS). D. Average voltage

C. Root mean square (RMS).

3-7A6 What type of wave is characterized by a rise time significantly faster than the fall time (or vice versa)? A. Cosine wave. B. Square wave. C. Sawtooth wave. D. Sine wave.

C. Sawtooth wave.

3-4A2 Good conductors with minimum resistance have what type of electrons? A. Few free electrons. B. No electrons. C. Some free electrons. D. Many free electrons.

D. Many free electrons.

3-3A2 What is the relative dielectric constant for air? A. 1 B. 2 C. 4 D. 0

A. 1

3-10B6 What is the maximum rated current-carrying capacity of a resistor marked "2000 ohms, 200 watts"? A. 0.316 amps. B. 3.16 amps. C. 10 amps. D. 100 amps.

A. 0.316 amps.

3-12B3 At 240 degrees, what is the amplitude of a sine-wave having a peak value of 5 volts? A. -4.3 volts. B. -2.5 volts. C. +2.5 volts. D. +4.3 volts.

A. -4.3 volts.

3-13B4 In a circuit where the AC voltage and current are out of phase, how can the true power be determined? A. By multiplying the apparent power times the power factor. B. By subtracting the apparent power from the power factor. C. By dividing the apparent power by the power factor. D. By multiplying the RMS voltage times the RMS current.

A. By multiplying the apparent power times the power factor.

3-13B2 If a resistance to which a constant voltage is applied is halved, what power dissipation will result? A. Double. B. Halved. C. Quadruple. D. Remain the same.

A. Double.

3-4A3 Which of the 4 groups of metals listed below are the best low-resistance conductors? A. Gold, silver, and copper. B. Stainless steel, bronze, and lead. C. Iron, lead, and nickel. D. Bronze, zinc, and manganese.

A. Gold, silver, and copper.

3-1A3 What is the term used to express the amount of electrical energy stored in an electrostatic field? A. Joules. B. Coulombs. C. Watts. D. Volts.

A. Joules

3-5A4 What are the two basic types of junction field-effect transistors? A. N-channel and P-channel. B. High power and low power. C. MOSFET and GaAsFET. D. Silicon FET and germanium FET.

A. N-channel and P-channel.

3-3A4 Skin effect is the phenomenon where: A. RF current flows in a thin layer of the conductor, closer to the surface, as frequency increases. B. RF current flows in a thin layer of the conductor, closer to the surface, as frequency decreases. C. Thermal effects on the surface of the conductor increase the impedance. D. Thermal effects on the surface of the conductor decrease the impedance.

A. RF current flows in a thin layer of the conductor, closer to the surface, as frequency increases.

3-7A5 What type of wave is made up of sine waves at the fundamental frequency and all the harmonics? A. Sawtooth wave. B. Square wave. C. Sine wave. D. Cosine wave.

A. Sawtooth wave.

3-8A4 Which of the following groups is correct for listing common materials in order of descending conductivity? A. Silver, copper, aluminum, iron, and lead. B. Lead, iron, silver, aluminum, and copper. C. Iron, silver, aluminum, copper, and silver. D. Silver, aluminum, iron, lead, and copper.

A. Silver, copper, aluminum, iron, and lead.

3-7A3 What type of wave is made up of sine waves of the fundamental frequency and all the odd harmonics? A. Square. B. Sine. C. Cosine. D. Tangent.

A. Square.

3-12B2 At 150 degrees, what is the amplitude of a sine-wave having a peak value of 5 volts? A. -4.3 volts. C. +2.5 volts. B. -2.5 volts. D. +4.3 volts.

B. -2.5 volts.

3-13B6 What does the power factor equal in an R-L circuit having a 30 degree phase angle between the voltage and the current? A. 1.73 B. 0.866 C. 0.5 D. 0.577

B. 0.866

3-14B6 After two time constants, the capacitor in an RC circuit is discharged to what percentage of the starting voltage? A. 86.5 % B. 13.5 % C. 63.2 % D. 36.8 %

B. 13.5 %

3-17B2 In polar coordinates, what is the impedance of a network composed of a 100-ohm-reactance inductor in series with a 100-ohm resistor? A. 121 ohms, /35 degrees B. 141 ohms, /45 degrees C. 161 ohms, /55 degrees D. 181 ohms, /65 degrees

B. 141 ohms, /45 degrees

3-11B5 What is the most the actual transmitter frequency could differ from a reading of 156,520,000 Hertz on a frequency counter with a time base accuracy of +/- 10 ppm? A. 146.52 Hz. B. 1565.20 Hz. C. 10 Hz. D. 156.52 kHz.

B. 1565.20 Hz.

3-16B4 In rectangular coordinates, what is the impedance of a network composed of a 1.0-millihenry inductor in series with a 200-ohm resistor, at 30 kHz? A. 200 - j188 B. 200 + j188 C. 188 + j200 D. 188 - j200

B. 200 + j188

3-12B5 What is the RMS value of a 340-volt peak-to-peak pure sine wave? A. 170 volts AC. C. 120 volts AC. B. 240 volts AC. D. 350 volts AC.

B. 240 volts AC.

3-9B5 If a current of 3 amperes flows through a resistor connected to 90 volts, what is the resistance? A. 3 ohms. B. 30 ohms. C. 93 ohms. D. 270 ohms.

B. 30 ohms.

3-10B3 A 500-ohm, 2-watt resistor and a 1500-ohm, 1-watt resistor are connected in parallel. What is the maximum voltage that can be applied across the parallel circuit without exceeding wattage ratings? A. 22.4 volts. B. 31.6 volts. C. 38.7 volts. D. 875 volts.

B. 31.6 volts.

3-7A1 What is a sine wave? A. A constant-voltage, varying-current wave. B. A wave whose amplitude at any given instant can be represented by the projection of a point on a wheel rotating at a uniform speed. C. A wave following the laws of the trigonometric tangent function. D. A wave whose polarity changes in a random manner.

B. A wave whose amplitude at any given instant can be represented by the projection of a point on a wheel rotating at a uniform speed.

3-12B6 Determine the phase relationship between the two signals shown in Figure 3B3. A. A is lagging B by 90 degrees. B. B is lagging A by 90 degrees. C. A is leading B by 180 degrees. D. B is leading A by 90 degrees.

B. B is lagging A by 90 degrees.

3-4A5 How would you calculate the total capacitance of three capacitors in parallel? A. CT = C1 + C2 / C1 - C2 + C3. B. CT = C1 + C2 + C3. C. CT = C1 + C2 / C1 x C2 + C3. D. CT = 1 / C1+1 / C2 + 1 / C3.

B. CT = C1 + C2 + C3.

3-6A1 An AC ammeter indicates: A. Effective (TRM) values of current. B. Effective (RMS) values of current. C. Peak values of current. D. Average values of current.

B. Effective (RMS) values of current.

3-9B2 Which of the following Ohms Law formulas is incorrect? A. I = E / R B. I = R / E C. E = I x R D. R = E / I

B. I = R / E

3-8A2 What happens to reactive power in a circuit that has both inductors and capacitors? A. It is dissipated as heat in the circuit. B. It alternates between magnetic and electric fields and is not dissipated. C. It is dissipated as inductive and capacitive fields. D. It is dissipated as kinetic energy within the circuit.

B. It alternates between magnetic and electric fields and is not dissipated.

3-5A2 What limits the maximum forward current in a junction diode? A. The peak inverse voltage (PIV). B. The junction temperature. C. The forward voltage. D. The back EMF.

B. The junction temperature.

3-8A6 Assuming a power source to have a fixed value of internal resistance, maximum power will be transferred to the load when: A. The load impedance is greater than the source impedance. B. The load impedance equals the internal impedance of the source. C. The load impedance is less than the source impedance. D. The fixed values of internal impedance are not relative to the power source.

B. The load impedance equals the internal impedance of the source.

3-2A6 Permeability is defined as: A. The magnetic field created by a conductor wound on a laminated core and carrying current. B. The ratio of magnetic flux density in a substance to the magnetizing force that produces it. C. Polarized molecular alignment in a ferromagnetic material while under the influence of a magnetizing force. D. None of these.

B. The ratio of magnetic flux density in a substance to the magnetizing force that produces it.

3-1A2 What is the basic unit of electrical power? A. Ohm. B. Watt. C. Volt. D. Ampere.

B. Watt.

3-1A5 What formula would determine the inductive reactance of a coil if frequency and coil inductance are known? A. XL = f L B. XL = 2 f L C. XL = 1 / 2 f C D. XL = 1 / R2+X2

B. XL = 2 f L

3-13B1 What does the power factor equal in an R-L circuit having a 60 degree phase angle between the voltage and the current? A. 0.414 B. 0.866 C. 0.5 D. 1.73

C. 0.5

3-6A5 By what factor must the voltage measured in an AC circuit, as indicated on the scale of an AC voltmeter, be multiplied to obtain the average voltage value? A. 0.707 B. 1.414 C. 0.9 D. 3.14

C. 0.9

3-6A2 By what factor must the voltage of an AC circuit, as indicated on the scale of an AC voltmeter, be multiplied to obtain the peak voltage value? A. 0.707 B. 0.9 C. 1.414 D. 3.14

C. 1.414

3-11B4 What is the most the actual transmitter frequency could differ from a reading of 156,520,000 hertz on a frequency counter with a time base accuracy of ± 1.0 ppm? A. 165.2 Hz. B. 15.652 kHz. C. 156.52 Hz. D. 1.4652 MHz.

C. 156.52 Hz.

3-16B5 In rectangular coordinates, what is the impedance of a network composed of a 0.01-microfarad capacitor in parallel with a 300-ohm resistor, at 50 kHz? A. 150 - j159 B. 150 + j159 C. 159 - j150 D. 159 + j150

C. 159 - j150

3-6A3 What is the RMS voltage at a common household electrical power outlet? A. 331-V AC. B. 82.7-V AC. C. 165.5-V AC. D. 117-V AC.

C. 165.5-V AC.

3-16B1 What is the impedance of a network composed of a 0.1-microhenry inductor in series with a 20-ohm resistor, at 30 MHz? Specify your answer in rectangular coordinates. A. 20 -j19 B. 19 +j20 C. 20 +j19 D. 19 -j20

C. 20 +j19

3-10B2 What is the maximum DC or RMS voltage that may be connected across a 20 watt, 2000 ohm resistor? A. 10 volts. B. 100 volts. C. 200 volts. D. 10,000 volts.

C. 200 volts.

3-17B3 In polar coordinates, what is the impedance of a network composed of a 400-ohm-reactance capacitor in series with a 300-ohm resistor? A. 240 ohms, /36.9 degrees B. 240 ohms, /-36.9 degrees C. 500 ohms, /-53.1 degrees D. 500 ohms, /53.1 degrees

C. 500 ohms, /-53.1 degrees

3-14B5 After two time constants, the capacitor in an RC circuit is charged to what percentage of the supply voltage? A. 36.8 % B. 63.2 % C. 86.5 % D. 95 %

C. 86.5 %

3-2A2 What will produce a magnetic field? A. A DC source not connected to a circuit. B. The presence of a voltage across a capacitor. C. A current flowing through a conductor. D. The force that drives current through a resistor.

C. A current flowing through a conductor

3-2A5 What is meant by the term "back EMF"? A. A current equal to the applied EMF. B. An opposing EMF equal to R times C (RC) percent of the applied EMF. C. A voltage that opposes the applied EMF. D. A current that opposes the applied EMF.

C. A voltage that opposes the applied EMF

3-1A4 What device is used to store electrical energy in an electrostatic field? A. Battery. B. Transformer. C. Capacitor. D. Inductor.

C. Capacitor.

3-14B4 What is the meaning of the term "time constant of an RL circuit"? The time required for the: A. Current in the circuit to build up to 36.8% of the maximum value. B. Voltage in the circuit to build up to 63.2% of the maximum value. C. Current in the circuit to build up to 63.2% of the maximum value. D. Voltage in the circuit to build up to 36.8% of the maximum value.

C. Current in the circuit to build up to 63.2% of the maximum value.

3-8A3 Halving the cross-sectional area of a conductor will: A. Not affect the resistance. B. Quarter the resistance. C. Double the resistance. D. Halve the resistance.

C. Double the resistance.

3-4A4 What is the purpose of a bypass capacitor? A. It increases the resonant frequency of the circuit. B. It removes direct current from the circuit by shunting DC to ground. C. It removes alternating current by providing a low impedance path to ground. D. It forms part of an impedance transforming circuit.

C. It removes alternating current by providing a low impedance path to ground.

3-5A3 MOSFETs are manufactured with THIS protective device built into their gate to protect the device from static charges and excessive voltages: A. Schottky diode. B. Metal oxide varistor (MOV). C. Zener diode. D. Tunnel diode.

C. Zener diode.

3-3A1 What metal is usually employed as a sacrificial anode for corrosion control purposes? A. Platinum bushing. B. Lead bar. C. Zinc bar. D. Brass rod.

C. Zinc bar.

3-12B1 At pi/3 radians, what is the amplitude of a sine-wave having a peak value of 5 volts? A. -4.3 volts. B. -2.5 volts. C. +2.5 volts. D. +4.3 volts

D. +4.3 volts

3-13B5 What does the power factor equal in an R-L circuit having a 45 degree phase angle between the voltage and the current? A. 0.866 B. 1.0 C. 0.5 D. 0.707

D. 0.707

3-9B3 If a current of 2 amperes flows through a 50-ohm resistor, what is the voltage across the resistor? A. 25 volts. B. 52 volts. C. 200 volts. D. 100 volts

D. 100 volts

3-6A6 What is the peak voltage at a common household electrical outlet? A. 234 volts. B. 117 volts. C. 331 volts. D. 165.5 volts.

D. 165.5 volts.

3-10B1 What is the peak-to-peak RF voltage on the 50 ohm output of a 100 watt transmitter? A. 70 volts. B. 100 volts. C. 140 volts. D. 200 volts.

D. 200 volts.

3-15B1 What is the time constant of a circuit having two 220-microfarad capacitors and two 1-megohm resistors all in parallel? A. 22 seconds. B. 44 seconds. C. 440 seconds. D. 220 seconds.

D. 220 seconds.

3-17B1 What is the impedance of a network composed of a 100-picofarad capacitor in parallel with a 4000-ohm resistor, at 500 KHz? Specify your answer in polar coordinates. A. 2490 ohms, /51.5 degrees B. 4000 ohms, /38.5 degrees C. 5112 ohms, /-38.5 degrees D. 2490 ohms, /-51.5 degrees

D. 2490 ohms, /-51.5 degrees

3-16B2 In rectangular coordinates, what is the impedance of a network composed of a 0.1-microhenry inductor in series with a 30-ohm resistor, at 5 MHz? A. 30 -j3 B. 3 +j30 C. 3 -j30 D. 30 +j3

D. 30 +j3

3-7A2 How many degrees are there in one complete sine wave cycle? A. 90 degrees. B. 270 degrees. C. 180 degrees. D. 360 degrees.

D. 360 degrees.

3-16B6 In rectangular coordinates, what is the impedance of a network composed of a 0.001-microfarad capacitor in series with a 400-ohm resistor, at 500 kHz? A. 318 - j400 B. 400 + j318 C. 318 + j400 D. 400 - j318

D. 400 - j318

3-11B6 What is the most the actual transmitter frequency could differ from a reading of 462,100,000 hertz on a frequency counter with a time base accuracy of ± 1.0 ppm? A. 46.21 MHz. B. 10 Hz. C. 1.0 MHz. D. 462.1 Hz.

D. 462.1 Hz.

3-14B2 What is the meaning of the term "time constant of an RC circuit"? The time required to charge the capacitor in the circuit to: A. 23.7% of the supply voltage. B. 36.8% of the supply voltage. C. 57.3% of the supply voltage. D. 63.2% of the supply voltage.

D. 63.2% of the supply voltage.

3-10B5 In Figure 3B2, what is the voltage drop across R1? A. 1.2 volts. B. 2.4 volts. C. 3.7 volts. D. 9 volts.

D. 9 volts.

3-7A4 What is the description of a square wave? A. A wave with only 300 degrees in one cycle. B. A wave whose periodic function is always negative. C. A wave whose periodic function is always positive. D. A wave that abruptly changes back and forth between two voltage levels and stays at these levels for equal amounts of time.

D. A wave that abruptly changes back and forth between two voltage levels and stays at these levels for equal amounts of time.

3-3A5 Corrosion resulting from electric current flow between dissimilar metals is called: A. Electrolysis. B. Stray current corrosion. C. Oxygen starvation corrosion. D. Galvanic corrosion

D. Galvanic corrosion

3-5A1 What are the two most commonly-used specifications for a junction diode? A. Maximum forward current and capacitance. B. Maximum reverse current and PIV (peak inverse voltage). C. Maximum reverse current and capacitance. D. Maximum forward current and PIV (peak inverse voltage).

D. Maximum forward current and PIV (peak inverse voltage).

3-8A5 How do you compute true power (power dissipated in the circuit) in a circuit where AC voltage and current are out of phase? A. Multiply RMS voltage times RMS current. B. Subtract apparent power from the power factor. C. Divide apparent power by the power factor. D. Multiply apparent power times the power factor.

D. Multiply apparent power times the power factor.

3-13B3 746 watts, corresponding to the lifting of 550 pounds at the rate of one-foot-per-second, is the equivalent of how much horsepower? A. One-quarter horsepower. B. One-half horsepower. C. Three-quarters horsepower. D. One horsepower.

D. One horsepower.

3-1A6 What is the term for the out-of-phase power associated with inductors and capacitors? A. Effective power. B. True power. C. Peak envelope power. D. Reactive power.

D. Reactive power.

3-2A4 The opposition to the creation of magnetic lines of force in a magnetic circuit is known as: A. Eddy currents. B. Hysteresis. C. Permeability. D. Reluctance.

D. Reluctance

3-3A3 Which metal object may be least affected by galvanic corrosion when submerged in seawater? A. Aluminum outdrive. B. Bronze through-hull. C. Exposed lead keel. D. Stainless steel propeller shaft.

D. Stainless steel propeller shaft.

3-12B4 What is the equivalent to the root-mean-square value of an AC voltage? A. AC voltage is the square root of the average AC value. B. The DC voltage causing the same heating in a given resistor at the peak AC voltage. C. The AC voltage found by taking the square of the average value of the peak AC voltage. D. The DC voltage causing the same heating in a given resistor as the RMS AC voltage of the same value.

D. The DC voltage causing the same heating in a given resistor as the RMS AC voltage of the same value.

3-2A1 What determines the strength of the magnetic field around a conductor? A. The resistance divided by the current. B. The ratio of the current to the resistance. C. The diameter of the conductor. D. The amount of current.

D. The amount of current.

3-2A3 When induced currents produce expanding magnetic fields around conductors in a direction that opposes the original magnetic field, this is known as: A. Lenz's law. B. Gilbert's law. C. Maxwell's law. D. Norton's law.

Lenz's law


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