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202 Cards in this Set

  • Front
  • Back
  • 3rd side (hint)
1] What is reactive power?

a} Wattless, non-productive power.

b} Power consumed in wire resistance in an inductor.

c} Power lost because of capacitor leakage.

d} Power consumed in circuit Q.
a} Wattless, non-productive power.
2] What is the term for an out-of-phase, non-productive power
associated with inductors and capacitors?

a} Effective power.

b} True power.

c} Peak envelope power.

d} Reactive power.
d} Reactive power.
3] What is the term for energy that is stored in an
electromagnetic or electrostatic field?

a} Potential energy.

b} Amperes-joules.

c} Joules-coulombs.

d} Kinetic energy.
a} Potential energy.
4] What is responsible for the phenomenon when voltages across
reactances in series can often be larger than the voltages
applied to them?

a} Capacitance.

b} Resonance.

c} Conductance.

d} Resistance.
b} Resonance.
5] What is resonance in an electrical circuit?

a} The highest frequency that will pass current.


b} The lowest frequency that will pass current.

c} The frequency at which capacitive reactance equals inductive
reactance.

d} The frequency at which power factor is at a minimum
c} The frequency at which capacitive reactance equals inductive
reactance.
6] Under what conditions does resonance occur in an electrical
circuit?

a} When the power factor is at a minimum.

b} When inductive and capacitive reactances are equal.

c} When the square root of the sum of the capacitive and
inductive reactances is equal to the resonant frequency.

d} When the square root of the product of the capacitive and
inductive reactances is equal to the resonant frequency.
b} When inductive and capacitive reactances are equal.
7] What is the term for the phenomena that occurs in an
electrical circuit when the inductive reactance equals the
capacitive reactance?

a} Reactive quiescence.

b} High Q.

c} Reactive equilibrium.

d} Resonance.
d} Resonance.
8] What is the approximate magnitude of the impedance of a
series R-L-C circuit at resonance?

a} High, as compared to the circuit resistance.

b} Approximately equal to the circuit resistance.

c} Approximately equal to XL.

d} Approximately equal to XC.
b} Approximately equal to the circuit resistance.
9] What is the approximate magnitude of the impedance of a
parallel R-L-C circuit at resonance?

a} Approximately equal to the circuit resistance.

b} Approximately equal to XL.


c} Low, as compared to the circuit resistance.

d} Approximately equal to XC.
a} Approximately equal to the circuit resistance.
10] What is the characteristic of the current flow in a series
R-L-C circuit at resonance?

a} It is at a minimum.

b} It is at a maximum.

c} It is DC.

d} It is zero.
b} It is at a maximum.
11] What is the characteristic of the current flow in a
parallel R-L-C circuit at resonance?

a} The current circulating in the parallel elements is at a
minimum.

b} The current circulating in the parallel elements is at a
maximum.

c} The current circulating in the parallel elements is DC.

d} The current circulating in the parallel elements is zero.
b} The current circulating in the parallel elements is at a
maximum.
12] What is the skin effect?

a} The phenomenon where RF current flows in a thinner layer of
the conductor, close to the surface, as frequency increases.

b} The phenomenon where RF current flows in a thinner layer of
the conductor, close to the surface, as frequency decreases.

c} The phenomenon where thermal effects on the surface of the
conductor increase the impedance.

d} The phenomenon where thermal effects on the surface of the
conductor decrease the impedance.
a} The phenomenon where RF current flows in a thinner layer of
the conductor, close to the surface, as frequency increases.
13] What is the term for the phenomenon where most of an RF
current flows along the surface of the conductor?

a} Layer effect.

b} Seeburg Effect.

c} Skin effect.

d} Resonance.
c} Skin effect.
14] Where does practically all of the RF current flow in a
conductor?

a} Along the surface.

b} In the center of the conductor.

c} In the magnetic field around the conductor.

d} In the electromagnetic field in the conductor center.
a} Along the surface.
15] Why does practically all of an RF current flow within a
few thousandths-of-an-inch of the conductor's surface?

a} Because of skin effect.

b} Because the RF resistance of the conductor is much less than
the DC resistance.

c} Because of heating of the metal at the conductor's interior.

d} Because of the AC-resistance of the conductor's self
inductance.
a} Because of skin effect.
16] Why is the resistance of a conductor different for RF
current than for DC?

a} Because the insulation conducts current at radio frequencies.

b} Because of the Heisenburg Effect.

c} Because of skin effect.

d} Because conductors are non-linear devices.
c} Because of skin effect.
17] What is a magnetic field?

a} Current flow through space around a permanent magnet.

b} A force set up when current flows through a conductor.

c} The force between the plates of a charged capacitor.

d} The force that drives current through a resistor.
b} A force set up when current flows through a conductor.
18] In what direction is the magnetic field about a conductor
when current is flowing?

a} In the same direction as the current.

b} In a direction opposite to the current flow.

c} In all directions; omnidirectional.

d} In a direction determined by the left hand rule.
d} In a direction determined by the left hand rule.
19] What device is used to store electrical energy in an
electrostatic field?

a} A battery.

b} A transformer.

c} A capacitor.

d} An inductor.
c} A capacitor.
20] What is the term used to express the amount of electrical
energy stored in an electrostatic field?

a} Coulombs.

b} Joules.

c} Watts.

d} Volts.
b} Joules.
21] What factors determine the capacitance of a capacitor?

a} Area of the plates, voltage on the plates and distance
between the plates.

b} Area of the plates, distance between the plates and the
dielectric constant of the material between the plates.

c} Area of the plates, voltage on the plates and the dielectric
constant of the material between the plates.

d} 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, distance between the plates and the
dielectric constant of the material between the plates.
22] What is the dielectric constant for air?

a} Approximately 1.


b} Approximately 2.

c} Approximately 4.

d} Approximately 0.
a} Approximately 1.
23] 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.
24] Why would the rate at which electrical energy is used in a
circuit be less than the product of the magnitudes of the AC
voltage and current?

a} Because there is a phase angle that is greater than zero
between the current and voltage.

b} Because there are only resistances in the circuit.

c} Because there are no reactances in the circuit.

d} Because there is a phase angle that is equal to zero between
the current and voltage.
a} Because there is a phase angle that is greater than zero
between the current and voltage.
25] 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.
26] What does the power factor equal in an R-L circuit having
a 60 degree phase angle between the voltage and the current?

a} 1.414.

b} 0.866.

c} 0.5.

d} 1.73.
c} 0.5.
27] 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.
28] 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} 0.5.
c} 0.866.
d} 0.577.
c} 0.866.
29] How many watts are being consumed in a circuit having a
power factor of 0.2 when the input is 100-V AC and 4-amperes is
being drawn?

a} 400 watts.

b} 80 watts.

c} 2000 watts.

d} 50 watts.
b} 80 watts.

Volts x Amps x Power Factor = True Power
30] How many watts are being consumed in a circuit having a
power factor of 0.6 when the input is 200-V AC and 5-amperes is
being drawn?

a} 200 watts.

b} 1000 watts.

c} 1600 watts.

d} 600 watts.
d} 600 watts.
Volts x Amps x Power Factor = True Power
31] What is the effective radiated power of a repeater with 50
watts transmitter power output, 4 dB feedline loss, 3 dB duplexer
and circulator loss, and 6 dB antenna gain?

a} 158 watts, assuming the antenna gain is referenced to a
half-wave dipole.

b} 39.7 watts, assuming the antenna gain is referenced to a
half-wave dipole.

c} 251 watts, assuming the antenna gain is referenced to a
half-wave dipole.

d} 69.9 watts, assuming the antenna gain is referenced to a
half-wave dipole.
b} 39.7 watts, assuming the antenna gain is referenced to a
half-wave dipole.
32] What is the effective radiated power of a repeater with 50
watts transmitter power output, 5 dB feedline loss, 4 dB duplexer
and circulator loss, and 7 dB antenna gain?

a} 300 watts, assuming the antenna gain is referenced to a
half-wave dipole.

b} 315 watts, assuming the antenna gain is referenced to a
half-wave dipole.

c} 31.5 watts, assuming the antenna gain is referenced to a
half-wave dipole.

d} 69.9 watts, assuming the antenna gain is referenced to a
half-wave dipole.
c} 31.5 watts, assuming the antenna gain is referenced to a
half-wave dipole.
33] What is the effective radiated power of a repeater with 75
watts transmitter power output, 4 dB feedline loss, 3 dB duplexer
and circulator loss, and 10 dB antenna gain?

a} 600 watts, assuming the antenna gain is referenced to a
half-wave dipole.

b} 75 watts, assuming the antenna gain is referenced to a
half-wave dipole.

c} 18.75 watts, assuming the antenna gain is referenced to a
half-wave dipole.

d} 150 watts, assuming the antenna gain is referenced to a
half-wave dipole.
d} 150 watts, assuming the antenna gain is referenced to a
half-wave dipole.
34] What is the effective radiated power of a repeater with 75
watts transmitter power output, 5 dB feedline loss, 4 dB duplexer
and circulator loss, and 6 dB antenna gain?

a} 37.6 watts, assuming the antenna gain is referenced to a
half-wave dipole.

b} 237 watts, assuming the antenna gain is referenced to a
half-wave dipole.

c} 150 watts, assuming the antenna gain is referenced to a
half-wave dipole.

d} 23.7 watts, assuming the antenna gain is referenced to a
half-wave dipole.
a} 37.6 watts, assuming the antenna gain is referenced to a
half-wave dipole.
35] What is the effective radiated power of a repeater with
100 watts transmitter power output, 4 dB feedline loss, 3 dB
duplexer and circulator loss, and 7 dB antenna gain?

a} 631 watts, assuming the antenna gain is referenced to a
half-wave dipole.

b} 400 watts, assuming the antenna gain is referenced to a
half-wave dipole.

c} 25 watts, assuming the antenna gain is referenced to a
half-wave dipole.

d} 100 watts, assuming the antenna gain is referenced to a
half-wave dipole.
d} 100 watts, assuming the antenna gain is referenced to a
half-wave dipole.
36] What is the effective radiated power of a repeater with
100 watts transmitter power output, 5 dB feedline loss, 4 dB
duplexer and circulator loss, and 10 dB antenna gain?

a} 800 watts, assuming the antenna gain is referenced to a
half-wave dipole.

b} 126 watts, assuming the antenna gain is referenced to a
half-wave dipole.

c} 12.5 watts, assuming the antenna gain is referenced to a
half-wave dipole.

d} 1260 watts, assuming the antenna gain is referenced to a
half-wave dipole.
b} 126 watts, assuming the antenna gain is referenced to a
half-wave dipole.
37] What is the effective radiated power of a repeater with
120 watts transmitter power output, 5 dB feedline loss, 4 dB
duplexer and circulator loss, and 6 dB antenna gain?

a} 601 watts, assuming the antenna gain is referenced to a
half-wave dipole.

b} 240 watts, assuming the antenna gain is referenced to a
half-wave dipole.

c} 60 watts, assuming the antenna gain is referenced to a
half-wave dipole.

d} 379 watts, assuming the antenna gain is referenced to a
half-wave dipole.
c} 60 watts, assuming the antenna gain is referenced to a
half-wave dipole.
38] What is the effective radiated power of a repeater with
150 watts transmitter power output, 4 dB feedline loss, 3 dB
duplexer and circulator loss, and 7 dB antenna gain?

a} 946 watts, assuming the antenna gain is referenced to a
half-wave dipole.

b} 37.5 watts, assuming the antenna gain is referenced to a
half-wave dipole.

c} 600 watts, assuming the antenna gain is referenced to a
half-wave dipole.

d} 150 watts, assuming the antenna gain is referenced to a
half-wave dipole.
d} 150 watts, assuming the antenna gain is referenced to a
half-wave dipole.
39] What is the effective radiated power of a repeater with
200 watts transmitter power output, 4 dB feedline loss, 4 dB
duplexer and circulator loss, and 10 dB antenna gain?

a} 317 watts, assuming the antenna gain is referenced to a
half-wave dipole.

b} 2000 watts, assuming the antenna gain is referenced to a
half-wave dipole.

c} 126 watts, assuming the antenna gain is referenced to a
half-wave dipole.

d} 260 watts, assuming the antenna gain is referenced to a
half-wave dipole.
a} 317 watts, assuming the antenna gain is referenced to a
half-wave dipole.
40] What is the effective radiated power of a repeater with
200 watts transmitter power output, 4 dB feedline loss, 3 dB
duplexer and circulator loss, and 6 dB antenna gain?

a} 252 watts, assuming the antenna gain is referenced to a
half-wave dipole.

b} 63.2 watts, assuming the antenna gain is referenced to a
half-wave dipole.

c} 632 watts, assuming the antenna gain is referenced to a
half-wave dipole.

d} 159 watts, assuming the antenna gain is referenced to a
half-wave dipole.
d} 159 watts, assuming the antenna gain is referenced to a
half-wave dipole.
41] What is the photoconductive effect?

a} The conversion of photon energy to electromotive energy.

b} The increased conductivity of an illuminated semiconductor
junction.

c} The conversion of electromotive energy to photon energy.

d} The decreased conductivity of an illuminated semiconductor
junction.
b} The increased conductivity of an illuminated semiconductor
junction.
42] What happens to photoconductive material when light shines
on it?

a} The conductivity of the material increases.

b} The conductivity of the material decreases.

c} The conductivity of the material stays the same.

d} The conductivity of the material becomes temperature
dependent.
a} The conductivity of the material increases.
43] What happens to the resistance of a photoconductive
material when light shines on it?

a} It increases.

b} It becomes temperature dependent.

c} It stays the same.

d} It decreases.
d} It decreases.
44] What happens to the conductivity of a semiconductor
junction when it is illuminated?

a} It stays the same.

b} It becomes temperature dependent.

c} It increases.

d} It decreases.
c} It increases.
45] What is an optocoupler?


a} A resistor and a capacitor.

b} A frequency modulated helium-neon laser.

c} An amplitude modulated helium-neon laser.

d} An LED and a phototransistor.
d} An LED and a phototransistor.
46] What is an optoisolator?

a} An LED and a phototransistor.

b} A P-N junction that develops an excess positive charge when
exposed to light.

c} An LED and a capacitor.

d} An LED and a solar cell.
a} An LED and a phototransistor.
47] What is an optical shaft encoder?

a} An array of optocouplers chopped by a stationary wheel.

b} An array of optocouplers whose light transmission path is
controlled by a rotating wheel.

c} An array of optocouplers whose propagation velocity is
controlled by a stationary wheel.

d} An array of optocouplers whose propagation velocity is
controlled by a rotating wheel.
b} An array of optocouplers whose light transmission path is
controlled by a rotating wheel.
48] What does the photoconductive effect in crystalline solids
produce a noticeable change in?

a} The capacitance of the solid.

b} The inductance of the solid.

c} The specific gravity of the solid.

d} The resistance of the solid.
d} The resistance of the solid.
49] What is the meaning of the term time constant of an RC
circuit?

a} The time required to charge the capacitor in the circuit to
36.8% of the supply voltage.

b} The time required to charge the capacitor in the circuit to
36.8% of the supply current.

c} The time required to charge the capacitor in the circuit to
63.2% of the supply current.

d} The time required to charge the capacitor in the circuit to
63.2% of the supply voltage.
d} The time required to charge the capacitor in the circuit to
63.2% of the supply voltage.
50] What is the meaning of the term time constant of an RL
circuit?

a} The time required for the current in the circuit to build up
to 36.8% of the maximum value.

b} The time required for the voltage in the circuit to build up
to 63.2% of the maximum value.

c} The time required for the current in the circuit to build up
to 63.2% of the maximum value.

d} The time required for the voltage in the circuit to build up
to 36.8% of the maximum value.
c} The time required for the current in the circuit to build up
to 63.2% of the maximum value.
51] 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.
52] 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.
53] What is the term for the time it takes for a charged
capacitor in an RC circuit to discharge to 36.8% of its initial
value of stored charge?

a} One discharge period.

b} An exponential discharge rate of one.

c} A discharge factor of one.

d} One time constant.
d} One time constant.
54] What is meant by 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 current that opposes the applied EMF.

d} A voltage that opposes the applied EMF.
d} A voltage that opposes the applied EMF.
55] 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%.
56] After two time constants, the capacitor in an RC circuit is
discharged to what percentage of the starting voltage?

a} 86.5%.

b} 63.2%.

c} 36.8%.

d} 13.5%.
d} 13.5%.
57] 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.

T (seconds)= R(ohms)x C (farads)
58] 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.

T (seconds)= R(ohms)x C (farads)
59] 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.

T (seconds)= R(ohms)x C (farads)
60] 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.

T (seconds)= R(ohms)x C (farads)
61] What is the time constant of a circuit having two
220-microfarad capacitors and two 1-megohm resistors all in
series?

a} 55 seconds.

b} 110 seconds.

c} 220 seconds.

d} 440 seconds.
c} 220 seconds.
62] 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} 220 seconds.

d} 440 seconds.
c} 220 seconds.
63] What is the time constant of a circuit having one
100-microfarad capacitor, one 220-microfarad capacitor, one
470-kilohm resistor and one 1-megohm resistor all in series?

a} 68.8 seconds.

b} 101.1 seconds.

c} 220.0 seconds.

d} 470.0 seconds.
b} 101.1 seconds.
64] What is the time constant of a circuit having a
470-microfarad capacitor and a 1-megohm resistor in parallel?

a} 0.47 seconds.

b} 47 seconds.

c} 220 seconds.

d} 470 seconds.
d} 470 seconds.
65] What is the time constant of a circuit having a
470-microfarad capacitor and a 470-kilohm resistor in series?

a} 221 seconds.

b} 221,000 seconds.

c} 470 seconds.

d} 470,000 seconds.
a} 221 seconds.
66] What is the time constant of a circuit having a
220-microfarad capacitor and a 470-kilohm resistor in series?

a} 103 seconds.

b} 220 seconds.

c} 470 seconds.

d} 470,000 seconds.
a} 103 seconds.
67] How long does it take for an initial charge of 20 V DC to
decrease to 7.36 V DC in a 0.01-microfarad capacitor when a
2-megohm resistor is connected across it?

a} 12.64 seconds.

b} 0.02 seconds.

c} 1 second.

d} 7.98 seconds.
b} 0.02 seconds.
68] How long does it take for an initial charge of 20 V DC to
decrease to 2.71 V DC in a 0.01-microfarad capacitor when a
2-megohm resistor is connected across it?

a} 0.04 seconds.

b} 0.02 seconds.

c} 7.36 seconds.

d} 12.64 seconds.
a} 0.04 seconds.
69] How long does it take for an initial charge of 20 V DC to
decrease to 1 V DC in a 0.01-microfarad capacitor when a 2-megohm
resistor is connected across it?

a} 0.01 seconds.

b} 0.02 seconds.

c} 0.04 seconds.

d} 0.06 seconds.
d} 0.06 seconds.
70] How long does it take for an initial charge of 20 V DC to
decrease to 0.37 V DC in a 0.01-microfarad capacitor when a
2-megohm resistor is connected across it?

a} 0.08 seconds.

b} 0.6 seconds.

c} 0.4 seconds.

d} 0.2 seconds.
a} 0.08 seconds.
71] How long does it take for an initial charge of 20 V DC to
decrease to 0.13 V DC in a 0.01-microfarad capacitor when a
2-megohm resistor is connected across it?

a} 0.06 seconds.

b} 0.08 seconds.

c} 0.1 seconds.

d} 1.2 seconds.
c} 0.1 seconds.
Each Time constant discharges Cap 63.2% of existing charge.

Time Constant = Resistance x Capacitance

Time Constant = Inductance / Resistance
72] How long does it take for an initial charge of 800 V DC to
decrease to 294 V DC in a 450-microfarad capacitor when a
1-megohm resistor is connected across it?

a} 80 seconds.

b} 294 seconds.

c} 368 seconds.

d} 450 seconds.
d} 450 seconds.
Each Time constant discharges Cap 63.2% of existing charge.

Time Constant = Resistance x Capacitance

Time Constant = Inductance / Resistance
73] How long does it take for an initial charge of 800 V DC to
decrease to 108 V DC in a 450-microfarad capacitor when a
1-megohm resistor is connected across it?

a} 225 seconds.

b} 294 seconds.

c} 450 seconds.

d} 900 seconds.
d} 900 seconds.
Each Time constant discharges Cap 63.2% of existing charge.

Time Constant = Resistance x Capacitance

Time Constant = Inductance / Resistance
74] How long does it take for an initial charge of 800 V DC to
decrease to 39.9 V DC in a 450-microfarad capacitor when a
1-megohm resistor is connected across it?

a} 1,350 seconds.

b} 900 seconds.

c} 450 seconds.

d} 225 seconds.
a} 1,350 seconds.
Each Time constant discharges Cap 63.2% of existing charge.

Time Constant = Resistance x Capacitance

Time Constant = Inductance / Resistance
75] How long does it take for an initial charge of 800 V DC to
decrease to 40.2 V DC in a 450-microfarad capacitor when a
1-megohm resistor is connected across it?

a} Approximately 225 seconds.

b} Approximately 450 seconds.

c} Approximately 900 seconds.

d} Approximately 1,350 seconds.
d} Approximately 1,350 seconds.
Each Time constant discharges Cap 63.2% of existing charge.

Time Constant = Resistance x Capacitance

Time Constant = Inductance / Resistance
76] How long does it take for an initial charge of 800 V DC to
decrease to 14.8 V DC in a 450-microfarad capacitor when a
1-megohm resistor is connected across it?

a} Approximately 900 seconds.

b} Approximately 1,350 seconds.

c} Approximately 1,804 seconds.

d} Approximately 2,000 seconds.
c} Approximately 1,804 seconds.
Each Time constant discharges Cap 63.2% of existing charge.

Time Constant = Resistance x Capacitance

Time Constant = Inductance / Resistance
77] 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} 20 - j19.

c} 19 + j20.

d} 19 - j20.
a} 20 + j19.
Inductive Reactance = 2 x pi x hertz x henries

Rectangle Coords:

R + J(Inductive Reactance) for Inductors

R - J(Capacitive Reactance) for Capacitors


Impedence = Square Root of (Ohms squared + Inductive Reactance squared)
78] What is the impedance of a network composed of a
0.1-microhenry inductor in series with a 30-ohm resistor, at 5
MHz? (Specify your answer in rectangular coordinates.)

a} 30 - j3.

b} 30 + j3.

c} 3 + j30.

d} 3 - j30.
b} 30 + j3.
Inductive Reactance = 2 x pi x hertz x henries

Rectangle Coords:

R + J(Inductive Reactance) for Inductors

R - J(Capacitive Reactance) for Capacitors


Impedence = Square Root of (Ohms squared + Inductive Reactance squared)
79] What is the impedance of a network composed of a
10-microhenry inductor in series with a 40-ohm resistor, at 500
MHz? (Specify your answer in rectangular coordinates.)

a} 40 + j31400.

b} 40 - j31400.

c} 31400 + j40.

d} 31400 - j40.
a} 40 + j31400.
Inductive Reactance = 2 x pi x hertz x henries

Rectangle Coords:

R + J(Inductive Reactance) for Inductors

R - J(Capacitive Reactance) for Capacitors


Impedence = Square Root of (Ohms squared + Inductive Reactance squared)
80] What is the impedance of a network composed of a
0.001-microfarad capacitor in series with a 400-ohm resistor, at
500 kHz? (Specify your answer in rectangular coordinates.)

a} 400 - j318.

b} 318 - j400.

c} 400 + j318.

d} 318 + j400.
a} 400 - j318.
Capacitive Reactance = 1 divided by ( 2 x pi x hertz x farads)

Rectangle Coords:

R + J(Inductive Reactance) for Inductors

R - J(Capacitive Reactance) for Capacitors
81] 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.
Inductance will create positive phase angle

Capacitance will create negative phase angle
82] What is the impedance of a network composed of a
100-ohm-reactance inductor in series with a 100-ohm resistor?
(Specify your answer in polar coordinates.)

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.
Inductance will create positive phase angle

Capacitance will create negative phase angle

If no frequency is called out (Reactance already calculated) the ohm value will be higher than the reactance given.
83] A nickel-cadmium cell has an operating voltage of about:

a} 1.25 volts.

b} 1.4 volts.

c} 1.5 volts.

d} 2.1 volts.
a} 1.25 volts.
84] What is the impedance of a network composed of a
400-ohm-reactance capacitor in series with a 300-ohm resistor?
(Specify your answer in polar coordinates.)

a} 240 ohms, / 36.9 degrees.

b} 240 ohms, / -36.9 degrees.

c} 500 ohms, / 53.1 degrees.

d} 500 ohms, / -53.1 degrees.
d} 500 ohms, / -53.1 degrees.
Inductance will create positive phase angle

Capacitance will create negative phase angle

If no frequency is called out (Reactance already calculated) the ohm value will be higher than the reactance given.

Remember the 3 -4 -5 relationship
85] 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? (Specify your answer
in polar coordinates.)

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.
Inductance will create positive phase angle

Capacitance will create negative phase angle

If no frequency is called out (Reactance already calculated) the ohm value will be higher than the reactance given.

Remember the 3 -4 -5 relationship
86] What is the impedance of a network composed of a
400-ohm-reactance inductor in parallel with a 300-ohm resistor?
(Specify your answer in polar coordinates.)

a} 240 ohms, / 36.9 degrees.

b} 240 ohms, / -36.9 degrees.

c} 500 ohms, / 53.1 degrees.

d} 500 ohms, / -53.1 degrees.
a} 240 ohms, / 36.9 degrees.
Inductance will create positive phase angle

Capacitance will create negative phase angle

If no frequency is called out (Reactance already calculated) the ohm value will be higher than the reactance given except for this problem.

Remember the 3 -4 -5 relationship
87] What is the impedance of a network composed of a
1.0-millihenry inductor in series with a 200-ohm resistor, at 30
kHz? (Specify your answer in rectangular coordinates.)

a} 200 - j188.

b} 200 + j188.

c} 188 + j200.

d} 188 - j200.
b} 200 + j188.
Remeber that Inductance creates a +J, capactiance creates a -J

Polar coords start out with the resistance value.
88] What is the impedance of a network composed of a
0.01-microfarad capacitor in parallel with a 300-ohm resistor, at
50 kHz? (Specify your answer in rectangular coordinates.)

a} 150 - j159.

b} 150 + j159.

c} 159 + j150.

d} 159 - j150.
d} 159 - j150.
Just memorize it!
89] Which of the following components is used in a power
supply circuit to allow filter capacitors to discharge when power
is turned off and aids in holding the voltage output more
constant?

a} Bleeder resistor.

b} Multiplier resistor.

c} Surge resistor.

d} Rectifying diodes.
a} Bleeder resistor.
90] A 1 watt, 10 volt zener diode with the following
characteristics: I min. = 5 mA, I max. = 95 mA, and Z = 8 ohms ;
is to be used as part of a voltage regulator. Approximately what
size current limiting resistor would set it's bias to the
midpoint of it's operating range?

a} 100 ohms.

b} 200 ohms.

c} 1 kilohms.

d} 2 kilohms.
b} 200 ohms.
Ignore Impedence.

Determine midpoint in diode operating Current

apply Ohms Law

R = E / I

91] A 1 watt, 10 volt zener diode with the following
characteristics: I min. = 5 mA, I max. = 480 mA, and Z = 3 ohms;
is to be used as part of a voltage regulator. Approximately what
size current limiting resistor would set it's bias to the
midpoint of it's operating range?

a} 40 ohms.

b} 100 ohms.

c} 400 ohms.

d} 1 kilohms.
a} 40 ohms.
Ignore Impedence
Determine middle value for diode Current

Use Ohms Law

R = E/I
92] A crowbar circuit is often added to a power supply to:

a} Prevent the circuit protective devices from being damaged.

b} Aide the filter section by increasing voltage regulation.

c} Protect the power supply by allowing the load to have as
much current as it needs.

d} Protect the load by activating circuit protective devices.
d} Protect the load by activating circuit protective devices.
93] Given a power supply with a no load voltage of 12 volts
and a full load voltage of 10 volts, what is the percentage of
voltage regulation?

a} 17 %.

b} 20 %.

c} 80 %.

d} 83 %.
b} 20 %.
94] Given a power supply with a full load voltage of 200
volts and a regulation of 25%, what is the no load voltage?.

a} 150 volts.

b} 160 volts.

c} 240 volts.

d} 250 volts.
d} 250 volts.
95] Given a power supply with a no load voltage of 200 volts
and a regulation of 25 %, what is the full load voltage.


a} 150 volts.

b} 160 volts.

c} 240 volts.

d} 250 volts.
b} 160 volts.
96] A 50 microampere meter movement has an internal
resistance of 2 kilohms. What applied voltage is required to
indicate half-scale deflection?

a} 0.01 Volts.

b} 0.10 Volts.

c} 0.005 Volts.

d} 0.05 Volts.
d} 0.05 Volts.
The amps given causes full meter deflection

Use Ohms Law

E = IR
97] The expression 'voltage regulation' as it applies to a
shunt-wound DC generator operating at a constant frequency refers
to:

a} Voltage output efficiency.

b} Voltage in the secondary compared to the primary.

c} Voltage fluctuations from load to no-load.

d} Rotor winding voltage ratio.
c} Voltage fluctuations from load to no-load.
98] When an emergency transmitter uses 325 watts and a
receiver uses 50 watts, how many hours can a 12.6 volt, 55
ampere-hour battery supply full power to both units?

a} 6 hours.

b} 3 hours.

c} 1.8 hours.

d} 1.2 hours.
c} 1.8 hours.
Use Ohms Law

P = IE
99] The expression "voltage regulation" as it applies to a
generator operating at a constant frequency refers to:

a} Full load to no load.

b} Limited load to peak load.

c} Source input supply frequency.

d} Field frequency.
a} Full load to no load.
100] The output of a separately excited AC generator running
at a constant speed can be controlled by:

a} Armature.

b} Brushes.

c} Field current.

d} Exciter.
c} Field current.
101] A transformer used to step up its input voltage must
have:

a} More turns of wire on its primary than on its secondary.

b} More turns of wire on its secondary than on its primary.

c} Equal number of primary and secondary turns of wire.

d} None of the above statements are correct.
b} More turns of wire on its secondary than on its primary.
102] A transformer used to step down its input voltage must
have:

a} More turns of wire on its primary than on its secondary.

b} More turns of wire on its secondary than on its primary.

c} Equal number of primary and secondary turns of wire.

d} None of the above statements are correct.
a} More turns of wire on its primary than on its secondary.
103] A 12.6 volt, 8 ampere-hour battery is supplying power to
a receiver that uses 50 watts and a radar system that uses 300
watts. How long will the battery last?

a} 100.8 hours.

b} 27.7 hours.

c} 1 hour.

d} 17 minutes or 0.3 hours.
d} 17 minutes or 0.3 hours.
It's easy as P = IE
104] What is the total voltage when 12 Nickel-Cadmium
batteries are connected in series?

a} 12 volts.

b} 12.6 volts.

c} 15 volts.

d} 72 volts.
c} 15 volts.
Nickel Cadium batteries operate at 1.25 v
105] A ship radar unit uses 315 watts and a radio uses 50
watts. If the equipment is connected to a 50 ampere-hour
battery rated at 12.6 volts, how long will the battery last?

a} 28.97 hours.

b} 29 minutes.

c} 1 hour 43 minutes.

d} 10 hours 50 minutes.
c} 1 hour 43 minutes.
Easy as P=IE
106] The turns ratio of a transformer is 1 : 20. When a 120
volt ac source is connected to its primary winding, the secondary
voltage is:

a} 120 Volts.

b} 1200 Volts.

c} 600 Volts.

d} 2400 Volts.
d} 2400 Volts.
Simple Ratio, just multiply
107] There is an improper impedance match between a 30 watt
transmitter and the antenna and 5 watts is reflected. How much
power is actually radiated?

a} 35 watts.

b} 30 watts.

c} 25 watts.

d} 20 watts.
c} 25 watts.
If it doesnt come back it must go out!
108] How long will a 12.6 volt, 50 ampere-hour battery last if
it supplies power to an emergency transmitter rated at 531 watts
of plate input power and other emergency equipment with a
combined power rating of 530 watts?

a} 6 hours.

b} 4 hours.

c} 1 hour.

d} 35 minutes.
d} 35 minutes.
Easy as P=IE
109] A 12.6 volt, 55 ampere-hour battery is connected to a
radar unit rated at 325 watts and a receiver that uses 20 watts.
How long will radar unit and receiver be able to draw full power
from the battery?

a} 6 hours.

b} 4 hours.

c} 2.3 hours.

d} 2 hours.
d} 2 hours.
Easy as P=IE
110] A power transformer has a 120 volt primary winding and
a 24 volt secondary winding. What is its turns ratio (referenced secondary to primary)?

a} 10 : 1.

b} 1 : 10.

c} 5 : 1.

d} 1 : 5.
d} 1 : 5.
Secondary goes first
111] A 6 volt battery with 1.2 ohms internal resistance is
connected across two 3 watt bulbs. What is the current flow?

a} .57 amps.

b} .83 amps.

c} 1.0 amps.

d} 6.0 amps.
b} .83 amps.
The light bulbs are in parallel
112] A power transformer has a primary winding of 200 turns
of #24 wire and a secondary winding consisting of 500 turns of
the same size wire. When 20 volts is applied to the primary
winding, the expected secondary voltage is:

a} 500 Volts.

b} 25 Volts.

c} 10 Volts.

d} 50 Volts.
d} 50 Volts.
113] The power input to a 52 ohm transmission line is 1,872
watts. The current flowing through the line is:

a} 6 amps.

b} 144 amps.

c} 0.06 amps.

d} 28.7 amps.
a} 6 amps.
I squared x R = P
114] If a marine radiotelephone receiver uses 75 watts of power
and a transmitter uses 325 watts, how long can they both operate
before discharging a 50 ampere-hour 12 volt battery?

a} 40 minutes.

b} 1 hour.

c} 1 1/2 hours.

d} 6 hours.
c} 1 1/2 hours.
easy as P=IE
115] A power transformer has a single primary winding and
three secondary windings producing 5.0 volts, 12.6 volts, and 150
volts. Which of the three secondary windings will have the
highest measured DC resistance.

a} The 12.6 volt winding.

b} The 5.0 volt winding.

c} The 150 volt winding.

d} All will have equal resistance values.
c} The 150 volt winding.
More turns = more wire = more resistance
116] Which of the following list 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.
SCAIL
117] Under what condition may gas be a good conductor?

a} When placed in an isotropic radiator.

b} When subjected to a vacuum.

c} When ionized.

d} When placed in a Leclanche' cell.
c} When ionized.
118] Ship's power is generated 3-phase, ungrounded. On a
delta-wound transformer with 120 Vac line-to-line secondary, the
voltmeter reading from line to ground is:

a} Approximately 67 Vac for a normal balanced system with no
faults.

b} 0 Vac for a system with that phase faulted to ground.

c} 120 Vac when another phase is faulted to ground.

d} None of these.
d} None of these.
There is no ground
119] The product of the number of turns and the current in
amperes used to describe relative magnitude is:

a} Ampere turns.

b} Joules per second.

c} Push-pull convergence.

d} Dissipation collection.
a} Ampere turns.
120] The factor by which the product of volts and amperes
must be multiplied to obtain true power is:

a} Apparent power.

b} Power factor.

c} Phase angle.

d} Power angle.
b} Power factor.
121] Halving the cross-sectional area of a conductor will:

a} Not affect the resistance.

b} Quarter the resistance.

c} Half the resistance.

d} Double the resistance.
d} Double the resistance.
122] If a resistance to which a constant voltage is applied
is halved, what power dissipation will result?

a} Doubled.

b} Halved.

c} Quadrupled.

d} Stay the same.
a} Doubled.
123] The effective value of an RF current and the heating
value of the current are:

a} Effective value divided by two equals the heating value.

b} Effective value multiplied by two equals the heating value.

c} The sum of the value of the divided parts multiplied by two
equals.

d} The same.
d} The same.
124] 746 watts, roughly 3/4 kilowatt corresponding to the
lifting of 550 pounds at the rate of one foot per second is:

a} Quarter of a horsepower.

b} Half of a horsepower.

c} 3/4 of a horsepower.

d} One horsepower.
d} One horsepower.
125] Assuming a power source to have a fixed value of
internal impedance, maximum power will be transferred to the load
when:

a} The load impedance equals the internal impedance of the
source.

b} The load impedance is greater than the source impedance.

c} The load impedance is less than the source impedance.

d} The fixed values of internal impedance is not relative to the
power source.
a} The load impedance equals the internal impedance of the
source.
126] What is the conductance (G) of a circuit if 6 amperes
of current flows when 12 Vdc is applied?

a} 0.25 siemens(mho).

b} 0.50 siemens(mho).

c} 1.00 siemens(mho).

d} 1.25 siemens(mho).
b} 0.50 siemens(mho).
G = I/E
127] If the voltage to a circuit is doubled and the
resistance is tripled, what will be the final current?

a} 1/3 the original current.

b} 2/3 the original current.

c} 1 1/3 the original current.

d} Double the original current.
b} 2/3 the original current.
I = E/R
128] 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 Vdc?

a} 150 ohms.

b} 220 ohms.

c} 380 ohms.

d} 470 ohms.
c} 380 ohms
Determine existing Voltage, then subtract that amount from desired total and use Ohms Law
129] How many capacitors of 400 volts and 2.0 microfarads each
would be necessary to obtain a combination rated at 1600 volts
and 1.5 microfarads?

a} 10.

b} 12.

c} 14.

d} 16.
b} 12.
130] The total inductance of two coils in parallel without
any mutual coupling is:

a} Equal to the product of the two inductances divided by their
sum.

b} Equal to the sum of the individual inductances.

c} Equal to zero.

d} Equal to the sum of the individual inductances divided by
their product.
a} Equal to the product of the two inductances divided by their
sum.
L1 x L2 / L1 + L2
131] Permeability is:

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.
132] What is the total impedance of a series AC circuit
having a resistance of 6 ohms, an inductive reactance of 17 ohms,
and zero capacitive reactance?

a} 6.6 ohms.

b} 11 ohms.

c} 18 ohms.

d} 23 ohms.
c} 18 ohms.
Square Root of R squared + X squared
133] The opposition to the creation of magnetic lines of
force in a magnetic circuit is known as:

a} Eddy currents.

b} Hysterisis.

c} Permeability.

d} Reluctance.
d} Reluctance.
134] Why is a center tap usually provided for vacuum tube
plate and grid return circuits when an AC filament supply is
used?

a} To prevent hum voltage from modulating the normal signals.

b} To allow more filament current.

c} All of these.

d} None of these.
a} To prevent hum voltage from modulating the normal signals.
135] Given the following vacuum tube constants: Gp = 1000V,
Ip = 150 mA, Ig = 10 mA, and grid leak = 5000 ohms; What would
be the grid bias voltage?

a} 25 V.

b} 50 V.

c} 100 V.

d} None of these.
b} 50 V.
Use Ohms Law
Ig = Grid Current
Grid Leak - Grid Resistance
136] A special type of power supply filter choke whose
inductance is inversely proportional to the amount of current
flowing through it is a:

a} AF choke.

b} RF choke.

c} Smoothing choke.

d} Swinging choke.
d} Swinging choke.
137] What turn ratio does a transformer need to match a
source impedance of 500 ohms to a load of 10 ohms.

a} 7.1 to 1.

b} 14.2 to 1.

c} 50 to 1.

d} None of these.
a} 7.1 to 1.
Square Root of Source Impedence / load Impedence
138] What is the DC plate voltage of a resistance-coupled
amplifier stage with a plate-supply voltage of 260 V, a plate
current of 1 mA, and a plate load resistance of 100 kilohms.

a} 60 volts.

b} 100 volts.

c} 160 volts.

d} 220 volts.
c} 160 volts.
Determine Existing Voltage Drop
139] The average fully charged voltage of an Edison storage
cell is:

a} 1 volt.

b} 1.2 volts.

c} 1.5 volts.

d} 2 volts.
b} 1.2 volts.
140] The average fully charged voltage of a lead-acid
storage cell is:

a} 1 volt.

b} 1.2 volts.

c} 1.56 volts.

d} 2.06 volts.
d} 2.06 volts.
141] A battery with a terminal voltage of 12.5 volts is to
be trickle-charged at a 0.5 A rate. What resistance should be
connected in series with the battery to charge it from a 110 Vdc
line?

a} 95 ohms.

b} 195 ohms.

c} 300 ohms.

d} None of these.
b} 195 ohms.
Voltage Drop then Ohms Law
142] A discharged storage cell of 3 cells has an
open-circuit voltage of 1.8 volts per cell and an internal
resistance of 0.1 ohms per cell. What voltage is needed to give
an initial charging rate of 10 A?

a} 8.4 volts.

b} 10 volts.

c} 12.5 volts.

d} 15 volts.
a} 8.4 volts.
143] What capacity in amperes does a storage battery need to
be in order to operate a 50 watt transmitter for 6 hours? Assume
a continuous transmitter load of 70% of the key-locked demand of
40 A, and an emergency light load of 1.5 A?

a} 100 ampere-hours.

b} 177 ampere-hours.

c} 249 ampere-hours.

d} None of these.
b} 177 ampere-hours.
Determine total Amps then multiply by hours
144] What current will flow in a 6 volt storage battery with
an internal resistance of 0.01 ohms, when a 3 watt, 6 volt lamp
is connected?

a} 0.4885 amps.

b} 0.4995 amps.

c} 0.5566 amps.

d} 0.5795 amps.
b} 0.4995 amps.
P = E squared x R
145] What is the ratio of the output frequency to the input
frequency of a single-phase full-wave rectifier?

a} 1 : 1.

b} 1 : 2.

c} 2 : 1.

d} None of these.
c} 2 : 1.
146] A capacitor is sometimes placed in series with the
primary of a power transformer to:

a} Improve the power factor.

b} Improve output voltage regulation.

c} To rectify the primary windings.

d} None of these.
a} Improve the power factor.
147] What is the maximum allowable secondary voltage of a
center-tapped transformer used in a full-wave rectifier with
tubes having a peak inverse voltage rating of 10,000 volts?

a} 5,000 volts.

b} 7,070 volts.

c} 10,000 volts.

d} 14,140 volts.
b} 7,070 volts.
RMS volts = Peak Volts x .707
148] A 3 horsepower, 100 Vdc motor is 85% efficient when
developing its rated output. What is the current?

a} 8.545 amps.

b} 20.345 amps.

c} 26.300 amps.

d} 25.000 amps.
c} 26.300 amps.
1 HP = 746

Watts given is output so you need to determine the input watts by dividing by the efficiency percentage

P = IE
I = P/E
149] What is the line current of a 7 horsepower motor
operating on 120 volts at full load, a power factor of 0.8, and
95% efficient?

a} 4.72 amps.

b} 13.03 amps.

c} 56 amps.

d} 57.2 amps.
d} 57.2 amps.
1 HP = 746

Watts given is output so you need to determine the input watts by dividing by the efficiency percentage and power factor.

P = IE
I = P/E
150] The second harmonic of a 380 kHz frequency is:

a} 2.

b} 190 kHz.

c} 760 kHz.

d} 144.4 GHz.
c} 760 kHz.
Multiply Carrier x Harmonic Number for Result
151] In a self-biased RF amplifier stage: plate voltage =
1250 volts, plate current = 150 mA, grid current = 15 mA, and
grid-leak resistance = 4000 ohms. What is the operating grid bias
voltage?

a} 30 volts.

b} 60 volts.

c} 187.5 volts.

d} 540 volts.
b} 60 volts.
Simple Ohms law using Grid data only
152] What would be the dB change in field intensity at a
given distance if the transmitter output power is doubled?

a} 1.5 dB.

b} 6 dB.

c} 2 dB.

d} 3 dB.
a} 1.5 dB.
153] If a field strength is 100 microvolts per meter at 100
miles, what is the field strength at 200 miles?

a} 10 microvolts.

b} 25 microvolts.

c} 50 microvolts.

d} 150 microvolts.
c} 50 microvolts.
Power is inversely proportiante to distance
154] What is the purpose of a multiplier resistor used with
a voltmeter?

a} A multiplier resistor is not used with a voltmeter.

b} It is used to increase the voltage indicating range of the
voltmeter.

c} It is used to decrease the voltage indicating range of the
voltmeter.


d} It is used to increase the current indicating range of an
ammeter not a voltmeter.
b} It is used to increase the voltage indicating range of the
voltmeter.
155] What is the purpose of a shunt resistor used with an
ammeter?

a} A shunt resistor is not used with an ammeter.

b} It is used to increase the ampere indicating range of the
ammeter.

c} It is used to decrease the ampere indicating range of the
ammeter.

d} It is used to increase the voltage indicating range of the
voltmeter not the ammeter.
b} It is used to increase the ampere indicating range of the
ammeter.
156] 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.
157] 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.
158] How may the range of a thermocouple ammeter be
increased?

a} By using a current transformer.

b} By using a capacitor shunt.

c} By using a current transformer and a capacitor shunt.

d} By using a resistor shunt.
c} By using a current transformer and a capacitor shunt.
159] By what factor must the voltage of an ac circuit, as
indicated on the scale of an ac voltmeter, be multiplied to
obtain the average voltage value?

a} 0.707.

b} 0.9.

c} 1.414.

d} 3.14.
b} 0.9.
160] 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.
161] What is the energy consumed by a radio receiver drawing
50 watts of power for 10 hours?

a} 500 joules.

b} 30000 joules.

c} 1800000 joules.

d} 30000 Ws.
c} 1800000 joules.
1 Joule = 1 watt second
162] What is the maximum rated current-carrying capacity of
a resistor marked "2000 ohms, 200 watts"?

a} .316 amps.

b} 3.16 amps.

c} 10 amps.

d} 100 amps.
a} .316 amps.
P = I squared x R
163] A radio receiver rated at 50 watts draws 1.5 amps from
the line. The effective resistance is:

a} 8.66 ohms.

b} 22.2 ohms.

c} 33.3 ohms.

d} 1.11 kilohms.
b} 22.2 ohms.
P = I squared x R
164] What is the maximum 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.
P x R = E squared
165] What is the resistance of a 60 watt, 117 volt lamp?

a} 1.95 ohms.

b} 2.76 ohms.

c} 30.8 ohms.

d} 228 ohms.
d} 228 ohms.
P x R = E squared
166] How much energy is used in a week by a 117 volt clock
having an internal resistance of 5000 ohms?

a} 19.2 watt-hours.

b} 134 watt-hours.

c} 460 watt-hours.

d} 27.6 kilowatt-hours.
c} 460 watt-hours.
Solve for I.
Then solve for P. Then multiply to week.
167] If.8 coulombs pass a point in a circuit in.8 seconds,
what is the average current value?

a} 1 ampere.

b} .640 amperes.

c} 1.28 amperes.

d} .414 amperes.
a} 1 ampere.
Amps = Coulombs per second
168] How much power is developed when 117 volts forces 11.7
coulombs through a point in a circuit in 1.17 seconds?

a} 8.55 watts.

b} 11.7 watts.

c} 1.17 k watts.

d} 1.6 kilowatts.
c} 1.17 k watts.
Amps = Coulombs per second
169] A 20 ohm, a 30 ohm, and an unknown-value resistor are
connected in series across a 140 volt source with.5 amps flowing
through the circuit. What is the unknown resistor's size?

a} 40 ohms.

b} 90 ohms.

c} 115 ohms.

d} 230 ohms.
d} 230 ohms.
Ohms Law
170] A 12 volt automotive battery with an internal
resistance of.2 ohms is connected to a 2 ohm headlight lamp.
What is the amount of current passing through the lamp?

a} 1.2 amperes.

b} 5.45 amperes.

c} 6 amperes.

d} None of these.
b} 5.45 amperes.
Ohms Law
171] What is the conductance of circuit having three 300 ohm
and two 200 ohm resistors connected in parallel?

a} 20 mS.

b} 50 ohms.

c} 8.33 mS.

d} 120 ohms.
a} 20 mS.
Conductance = 1/R

R in parallel =

1/R = 1/R1 + 1/R2 + 1/R3
172] 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.
Use P X R = E squared to determine max volts for each component, then pick the smaller one.
173] A 20 ohm and 30 ohm resistor form a parallel circuit
connected to a 12 volt source with an internal resistance of.2
ohms. Which of the following correctly represents Kirchoff's
voltage laws for the circuit in question assuming A is the current through the 30 ohm resistor
and B is the current through the 20 ohm resistor?

a} 12-.2A-20A-30B=0.

b} 12-.2A-20B=0.

c} 12-.2A-30A=0.

d} 12-.2A-20B=0 and 12-.2A-30A=0.
d} 12-.2A-20B=0 and 12-.2A-30A=0.
Kirchhoff's Voltage Law =

The Sum of all Voltage drops will be 0

174] If a complex circuit is reduced to an equivalent
circuit consisting of a single voltage source in series with a
single resistor, this is an example of:

a} Norton's theorem.

b} Thevenin's theorem.

c} Ohm's law.

d} Kirchoff's law.
b} Thevenin's theorem.
175] If a complex circuit is reduced to an equivalent
circuit consisting of a single current source in parallel with a
single resistor, this is an example of:

a} Norton's theorem.

b} Thevenin's theorem.

c} Ohm's law.

d} Kirchoff's law.
a} Norton's theorem.
176] If a 20 ohm resistor, a 30 ohm resistor, and a 12 volt
source with an internal resistance of 2 ohms are connected in a
parallel circuit arrangement, how much current will flow from the
source?

a} 0.240 amperes.

b} 0.857 amperes.

c} 0.750 amperes.

d} 1.000 amperes.
b} 0.857 amperes.
Calculate Resistance Values of the two parallel resistors, then add the internal resistance and use Ohms Law
177] If a current flowing through a coil produces 200 lines
of force in the core of the coil it can be said that the core
has:

a} Flux of 14.14 lines.

b} Flux of 100 lines.

c} 200 gauss.

d} 200 maxwells.
d} 200 maxwells.
1 maxwell = 1 line of force
178] If the core of a coil is 2 centimeters squared and has
200 lines of force in the core, it can be said that the core has:

a} Flux of 100.

b} Flux of 400.

c} 100 gauss.

d} 100 maxwells.
c} 100 gauss.
1 line per square centimeter = gauss
179] If a 50 turn coil has 2 amperes of current flowing
through it, one can say it has:

a} 79.6 gilberts.

b} 100 flux.

c} 100 gauss.

d} 79.6 oersted.
a} 79.6 gilberts.
Gilberts = 4 x pi x number of turns x current / 10
180] If a 50 turn coil has 2 amperes of current flowing
through it and a core length of 2 inches, one can say it has:

a} 24.75 gilberts.

b} 24.75 flux.


c} 24.75 gauss.

d} 24.75 oersted.
d} 24.75 oersted.
181] In comparing an electric circuit with a magnetic
circuit, volts is similar to ____, resistance is similar to ____,
and amperes is similar to ____.

a} Gilberts, reluctance, maxwells.

b} Reluctance, gilberts, maxwells.

c} Gilberts, maxwells, reluctance.

d} Maxwell, reluctance, gilberts.
a} Gilberts, reluctance, maxwells.
182] When magnetic lines are cut at a rate of ____ lines per
second, an average EMF of 1 volt is produced.

a} 10,000.

b} 100,000.

c} 10,000,000.

d} 100,000,000.
d} 100,000,000.
1 weber = 100,000,000
183] Which of the following would shield a permanent-magnet
field best?

a} Copper.

b} Iron.

c} Lead.

d} Aluminum.
b} Iron.
184] When induced currents produce expanding magnetic fields
around conductors in a direction that opposes the original
magnetic field, this is known as:

a} Gilbert's law.

b} Lenz's law.

c} Maxwells' law.

d} Norton's law.
b} Lenz's law.
185] At 240 degrees, what is the amplitude of 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.
186] At 150 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.
c} +2.5 volts.
187] 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.
pi = 180 degrees

180/3 = 60 degrees
188] If 4 amperes of current is flowing at 60 degrees, how
much will flow at 150 degrees?

a} 2.0 amperes.

b} 2.3 amperes.

c} 3.5 amperes.

d} 4.0 amperes.
b} 2.3 amperes.
189] If 4 amperes of current is flowing at 30 degrees, how
much will flow at 120 degrees?

a} 2.3 amperes.

b} 4.0 amperes.

c} 6.9 amperes.

d} 8.0 amperes.
c} 6.9 amperes.
190] The frequency that is 2 octaves higher than 1000 Hz is:

a} 2000 Hz.

b} 3000 Hz.

c} 4000 Hz.

d} 5000 Hz.
c} 4000 Hz.
1 octave = f x 2
191] Which of the following would be considered a
transducer?

a} Light emitting diode.

b} Vacuum tube filament.

c} Speaker.

d} Microphone.
d} Microphone.
192] What is the inductance in microhenries of a coil having
a diameter of 1/2 inch, a length of 1 inch, and 200 turns?

a} 25 microhenries.

b} 204 microhenries.

c} 305 microhenries.

d} 503 microhenries.
b} 204 microhenries.
Inductance = diameter (inches)squared x number of turns square / 18 x diameter + 40 x coil length in inches
193] If a 10 henry coil has 50 mA of current flowing through
it, how much energy is stored in the magnetic field?

a} 0.0125 Joules.

b} 12.5 Joules.

c} 0.500 Joules.

d} 500 Joules.
a} 0.0125 Joules.
Joules = Current squared x Inductance / 2
194] If two coils are close enough to have a mutual
inductance of.2 H and the coils have inductances of 2 H and 8 H,
what is the coefficient of coupling?

a} 2.5 %.

b} 5.0 %.

c} 10 %.

d} 25 %.
b} 5.0 %.
195] If a power transformer has a primary voltage of 120
Vac, a secondary voltage of 12 volts, and an efficiency of 95 %
when delivering 2 amperes of secondary current, what is the value
of primary current?

a} 190 milliamperes.

b} 200 milliamperes.

c} 211 milliamperes.

d} 2 amperes.
c} 211 milliamperes.
196] What is the capacitance of a capacitor with individual
plate area of 2 square inches each, an air dielectric, and
spacing between the two parallel plates of.01 inches?

a} 45 picofarads.

b} 45 microfarads.

c} 200 picofarads.

d} 200 microfarads.
a} 45 picofarads.
pico
197] What is the capacitance of a capacitor with individual
plate area of 1 square inch each, an air dielectric, and spacing
between the two parallel plates of.01 inches?


a} 2.25 picofarads.

b} 22.5 picofarads.

c} 2.25 microfarads.

d} 22.5 microfarads.
b} 22.5 picofarads.
pico
198] Which of the following materials has a dielectric
strength of approximately 80 volts?

a} Air.

b} Bakelite.

c} Glass.

d} Mica.
a} Air.
199] The electron difference between the plates of a 5
microfarad capacitor connected to 10 Vdc will be:

a} 0.000005 coulombs.

b} 0.00005 coulombs.

c} 31.2 Terra electrons.

d} 3.12 Terra electrons.
b} 0.00005 coulombs.
Charge = Capacitance x volts
200] If a series circuit consist of an inductor with an
inductive reactance of 57.7 ohms and a resistance of 100 ohms,
the phase angle between voltage and current will be
approximately:

a} 30 degrees.

b} 35 degrees.

c} 55 degrees.

d} 60 degrees.
a} 30 degrees.
Arctan (reactance/resistance)
201] If a series circuit consist of an inductor with an
inductive reactance of 100 ohms and a resistance of 57.7 ohms,
the phase angle between voltage and current will be
approximately:

a} 30 degrees.


b} 35 degrees.

c} 55 degrees.

d} 60 degrees.
d} 60 degrees.
phase angle = arctan(Reactance/resistance)
202] Approximately what capacitance value is needed to
resonate a 2.5 millihenry coil to 2.146 MHz?

a} 2.2 picofarads.

b} 2.2 microfarads.

c} 87 picofarads.

d} 87 microfarads.
a} 2.2 picofarads.