Avionics AC Test UPDATED ACTUAL
Exam Questions and CORRECT Answers
A coefficient of coupling of 0 indicates? - CORRECT ANSWER - No lines of flux cut the
secondary windings
Which section of an oscilloscope controls amplitude? - CORRECT ANSWER - Vertical
controls
A step-up transformer steps up? - CORRECT ANSWER - Voltage
Which control on an oscilloscope controls the brightness of the trace? - CORRECT
ANSWER - Intensity controls
When using the left hand rule for coils, what do the wrapped fingers represent? - CORRECT
ANSWER - Current flow
What formula would would calculate the total inductance of inductors in series? - CORRECT
ANSWER - Lt=L1+L2
What is the easiest voltage amplitude to measure by viewing a pure sine wave signal on an
oscilloscope? - CORRECT ANSWER - Peak-to-Peak
What is the impedance of a circuit containing a 1K OHMS resistor, a 2mh inductor and a
12.678microF capacitor in series operating at a frequency of 1Khz? - CORRECT ANSWER -
1K OHMS
To convert Peak-to-Peak voltage to RMS voltage. - CORRECT ANSWER - Peak-to-Peak
divided by 2 x .707
, What is the power factor of a circuit with true power of 5.10 watts and an apparent power of 9.85
volt amps? - CORRECT ANSWER - .52
Capacitive reactace will increase with a/an? - CORRECT ANSWER - Decrease in capacitance
and/or frequency
In a capacitive circuit - CORRECT ANSWER - Current leads voltage
In an AC circuit, where the voltage and current are out of phase, how can true power be
determined? - CORRECT ANSWER - By multiplying the apparent power times the power
factor
What happens to reactive power in a circuit that has both inductors and capacitors? - CORRECT
ANSWER - It is returned to the source and not dissipated
What is the meaning of the term time constant of an RC circuit? - CORRECT ANSWER -
The time required to charge the capacitor in the circuit to 63.2% of the supply voltage
What is the magnitude of the impedance of a series AC circuit having a resistance of 10 ohms, an
inductive reactance of 20 ohms, and zero capacitive reactance? - CORRECT ANSWER -
22.36 ohms
After two time constants, the capacitor in an RC circuit is discharged to what percentage of the
starting voltage? - CORRECT ANSWER - 13.5%
What factors determine the capacitance of a capacitor? - CORRECT ANSWER - Distance
between the plates and the dielectric constant of the material between the plates
What is the purpose of a coupling capacitor? - CORRECT ANSWER - It blocks DC and
passes AC
Exam Questions and CORRECT Answers
A coefficient of coupling of 0 indicates? - CORRECT ANSWER - No lines of flux cut the
secondary windings
Which section of an oscilloscope controls amplitude? - CORRECT ANSWER - Vertical
controls
A step-up transformer steps up? - CORRECT ANSWER - Voltage
Which control on an oscilloscope controls the brightness of the trace? - CORRECT
ANSWER - Intensity controls
When using the left hand rule for coils, what do the wrapped fingers represent? - CORRECT
ANSWER - Current flow
What formula would would calculate the total inductance of inductors in series? - CORRECT
ANSWER - Lt=L1+L2
What is the easiest voltage amplitude to measure by viewing a pure sine wave signal on an
oscilloscope? - CORRECT ANSWER - Peak-to-Peak
What is the impedance of a circuit containing a 1K OHMS resistor, a 2mh inductor and a
12.678microF capacitor in series operating at a frequency of 1Khz? - CORRECT ANSWER -
1K OHMS
To convert Peak-to-Peak voltage to RMS voltage. - CORRECT ANSWER - Peak-to-Peak
divided by 2 x .707
, What is the power factor of a circuit with true power of 5.10 watts and an apparent power of 9.85
volt amps? - CORRECT ANSWER - .52
Capacitive reactace will increase with a/an? - CORRECT ANSWER - Decrease in capacitance
and/or frequency
In a capacitive circuit - CORRECT ANSWER - Current leads voltage
In an AC circuit, where the voltage and current are out of phase, how can true power be
determined? - CORRECT ANSWER - By multiplying the apparent power times the power
factor
What happens to reactive power in a circuit that has both inductors and capacitors? - CORRECT
ANSWER - It is returned to the source and not dissipated
What is the meaning of the term time constant of an RC circuit? - CORRECT ANSWER -
The time required to charge the capacitor in the circuit to 63.2% of the supply voltage
What is the magnitude of the impedance of a series AC circuit having a resistance of 10 ohms, an
inductive reactance of 20 ohms, and zero capacitive reactance? - CORRECT ANSWER -
22.36 ohms
After two time constants, the capacitor in an RC circuit is discharged to what percentage of the
starting voltage? - CORRECT ANSWER - 13.5%
What factors determine the capacitance of a capacitor? - CORRECT ANSWER - Distance
between the plates and the dielectric constant of the material between the plates
What is the purpose of a coupling capacitor? - CORRECT ANSWER - It blocks DC and
passes AC
