G5A01
What is impedance?
A. The electric charge stored by a capacitor
B. The opposition to the flow of AC in a circuit
containing only capacitance
C. The opposition to the flow of AC in a circuit
D. The force of repulsion between one electric field and
another with the same charge
G5A02
What is reactance?
A. Opposition to DC caused by resistors
B. Opposition to AC caused by inductors and capacitors
C. A property of ideal resistors in AC circuits
D. A large spark produced at switch contacts when an
inductor is de-energized
G5A03
In an inductor, what causes opposition to the flow of AC?
A. Resistance
B. Reluctance
C. Admittance
D. Reactance
G5A04
In a capacitor, what causes opposition to the flow of AC?
A. Resistance
B. Reluctance
C. Reactance
D. Admittance
G5A05
How does a coil react to AC?
A. As the frequency of the applied AC increases, the
reactance decreases
B. As the amplitude of the applied AC increases, the
reactance increases
C. As the amplitude of the applied AC increases, the
reactance decreases
D. As the frequency of the applied AC increases, the
reactance increases
G5A06
How does a capacitor react to AC?
A. As the frequency of the applied AC increases, the
reactance decreases
B. As the frequency of the applied AC increases, the
reactance increases
C. As the amplitude of the applied AC increases, the
reactance increases
D. As the amplitude of the applied AC increases, the
reactance decreases
G5A07
What happens when the impedance of an electrical load is
equal to the internal impedance of the power source?
A. The source delivers minimum power to the load
B. The electrical load is shorted
C. No current can flow through the circuit
D. The source delivers maximum power to the load
G5A08
Why is impedance matching important?
A. So the source can deliver maximum power to the load
B. So the load will draw minimum power from the source
C. To ensure that there is less resistance than reactance
in the circuit
D. To ensure that the resistance and reactance in the
circuit are equal
G5A09
What unit is used to measure reactance?
A. Mho
B. Ohm
C. Ampere
D. Siemens
G5A10
What unit is used to measure impedance?
A. Volt
B. Ohm
C. Ampere
D. Watt
G5A11
Why should core saturation of a conventional impedance
matching transformer be avoided?
A. Harmonics and distortion could result from saturation
B. Magnetic flux would increase with frequency
C. RF susceptance would increase
D. Temporary changes of the core permeability could
result from saturation
G5B01
A two-times increase in power results in a change of how many dB?
A. 1 dB higher
B. 3 dB higher
C. 6 dB higher
D. 12 dB higher
G5B02
In a parallel circuit with a voltage source and several
branch resistors, how is the total current related to the
current in the branch resistors?
A. It equals the average of the branch current through
each resistor
B. It equals the sum of the branch current through each
resistor
C. It decreases as more parallel resistors are added to
the circuit
D. It is the sum of each resistor's voltage drop
multiplied by the total number of resistors
G5B03
How many watts of electrical power are used if 400 VDC is
supplied to an 800-ohm load?
A. 0.5 watts
B. 200 watts
C. 400 watts
D. 320,000 watts
G5B04
How many watts of electrical power are used by a 12-VDC
light bulb that draws 0.2 amperes?
A. 60 watts
B. 24 watts
C. 6 watts
D. 2.4 watts
G5B05
How many watts are being dissipated when 7.0 milliamperes
flow through 1.25 kilohms?
A. Approximately 61 milliwatts
B. Approximately 39 milliwatts
C. Approximately 11 milliwatts
D. Approximately 9 milliwatts
G5B06
What is the voltage across a 500-turn secondary winding in
a transformer if the 2250-turn primary is connected to 120
VAC?
A. 2370 volts
B. 540 volts
C. 26.7 volts
D. 5.9 volts
G5B07
What is the turns ratio of a transformer to match an audio
amplifier having a 600-ohm output impedance to a speaker
having a 4-ohm impedance?
A. 12.2 to 1
B. 24.4 to 1
C. 150 to 1
D. 300 to 1
G5B08
A DC voltage equal to what value of an applied sine-wave AC
voltage would produce the same amount of heat over time in
a resistive element?
A. The peak-to-peak value
B. The RMS value
C. The average value
D. The peak value
G5B09
What is the peak-to-peak voltage of a sine wave that has an
RMS voltage of 120 volts?
A. 84.8 volts
B. 169.7 volts
C. 204.8 volts
D. 339.4 volts
G5B10
A sine wave of 17 volts peak is equivalent to how many
volts RMS?
A. 8.5 volts
B. 12 volts
C. 24 volts
D. 34 volts
G5B12
What causes a voltage to appear across the secondary
winding of a transformer when a voltage source is connected
across its primary winding?
A. Capacitive coupling
B. Displacement current coupling
C. Mutual inductance
D. Mutual capacitance
G5B13
What would be the capacitance and voltage rating of a
series circuit consisting of two equal value capacitors
with equal voltage ratings?
A. Total capacitance would be half that of each capacitor
and maximum voltage would be twice that of each capacitor
B. Total capacitance would be half that of each capacitor
and maximum voltage would be the same as each capacitor
C. Total capacitance and maximum voltage would be the
same as each capacitor
D. Total capacitance and maximum voltage would be half
that of each capacitor
G5B14
What percentage loss would result from a transmission line
loss of 1 dB?
A. 16.6%
B. 12.5%
C. 14.7%
D. 20.6%
G5B15
If three equal resistors in parallel produce 50-ohms of
resistance and the same resistors in series produce 450-
ohms, what is the value of each resistor?
A. 1500-ohms
B. 90-ohms
C. 150-ohms
D. 175-ohms