electronics technician
posted by mompati on .
1. A circuit contains a 10 F capacitor and a 30 F capacitor connected in parallel. What is the total
capacitance of the circuit?
A. 7.5 F C. 40 F
B. 20 F D. 47 F
2. What is the time constant of a 2 mH inductor and a 200 resistor connected in series?
A. 10 msec C. 10 sec
B. 1 msec D. 1 sec
3. Which of the following dielectric materials has the highest dielectric constant?
A. Porcelain C. Paraffined paper
B. Oil D. Distilled water
4. What type of capacitor has great stability and is up to three times smaller than a standard electrolytic
capacitor?
A. Tantalum C. Mica
B. Paper D. Ceramic
5. What is the time constant of a 0.05 F capacitor connected in series with a 200 k resistor?
A. 1 s C. 0.01 s
B. 0.1 s D. 10 s
6. What is the total inductance of a circuit that contains two 10 H inductors connected in parallel?
A. 5 H C. 15 H
B. 8 H D. 20 H
7. An inductor stores a charge
A. in the electric field between its plates.
B. as a magnetic field in its dielectric.
C. as a magnetic field surrounding the conductor.
D. in an insulating material in the circuit.
8. If an RC circuit is supplied with 24 VDC and the circuit is in its third time constant, how much voltage
would be present across the capacitor?
A. 20.71 VDC C. 23.50 VDC
B. 22.77 VDC D. 22.80 VDC
9. What type of capacitor uses aluminum oxide as its dielectric?
A. Mica C. Paper
B. Ceramic D. Electrolytic
10. A circuit contains a 10 pF capacitor and a 50 pF capacitor connected in parallel. What is the total
capacitance of this circuit?
A. 8.3 pF C. 50 pF
B. 25 pF D. 60 pF
11. A circuit contains a 20 F capacitor and a 60 F capacitor connected in series. What is the total
capacitance of the circuit?
A. 12 F C. 30 F
B. 15 F D. 80 F
12. In an RC circuit, after which of the following time constants is a capacitor considered to be fully
charged?
A. The first C. The fifth
B. The third D. The fourth
13. What is the typical insulation resistance for a mica capacitor?
A. 1 M C. 1,000 M
B. 10 K D. 10,000
14. What type of meter is used to directly find the capacitance value of an unknown capacitor or to check
the condition of a known capacitor?
A. LCR meter C. Megohm meter
B. VOM meter D. Oscilloscope
15. An RC circuit contains a 1,000 resistor and a 0.1 F capacitor. What is the time constant of this
circuit?
A. 0.01 s C. 1 s
B. 0.0001 s D. 0.1 s
16. An electronic circuit has a 60 mH inductor and a 30 mH inductor connected in parallel. What is the
total inductance of the circuit?
A. 90 mH C. 35 mH
B. 75 mH D. 20 mH
17. Which of the following capacitor types has the lowest insulation resistance and therefore, the highest
leakage current?
A. Mica C. Electrolytic
B. Ceramic D. Tantalum
18. Which of the following values is equal to one picofarad?
A. 1 10–3 F C. 1 10–10 F
B. 1 10–6 F D. 1 10–12 F
19. On an electrolytic or paper capacitor, what does the black band indicate?
A. That the capacitor’s negative lead is near the band
B. That the capacitor has a value less than 10 mF
C. That the capacitor’s voltage rating is less than 100 VDC
D. That the capacitor is color coded to military specifications
20. A mica capacitor has in order, the color codes red, orange, and yellow. What is the capacitance value
of this capacitor in microfarads?
A. 0.23 F C. 23 F
B. 2.3 F D. 230 F
21. After the third time constant, what is the current in an inductor if the steady state circuit current is 10
amps?
A. 7.43 A C. 9.490 A
B. 8.60 A D. 10.00 A
22. What is the time constant of a 5 mH inductor and a 200 resistor connected in series?
A. 100 s C. 25 s
B. 10 s D. 0.25 s
23. What is the purpose of placing a large electrolytic capacitor in the output side of a power supply?
A. To rectify the AC current
B. To remove AC ripple from the DC output
C. To hold a charge after the supply is turned off
D. To prevent the DC from reversing polarity
24. An inductor can be placed in series with a motor to provide
A. braking for the motor.
B. heat reduction in the motor windings.
C. faster motor response to driver signals.
D. less current feedback to the driver.
25. What action should always be taken before working on a circuit with an electrolytic capacitor or another
large capacitor?
A. Disconnect the bleeder resistor.
B. Place the VOM’s leads directly to the capacitor.
C. Check the capacitor with an LCR meter.
D. Discharge the capacitor.

There is no way I will answer all of these. If you try yourself someone might help. The first one is just common sense. Capacitance is charge per unit voltage. With two capacitors in parallel they are both at the same voltage, so each has charge corresponding to that voltage, so you add the charges for the total charge per unit voltage. So C = C1 + C2 = 40 Farads

21. After the third time constant, what is the current in an inductor if the steady state circuit current is 10
amps?