Bookmark and Share

Front Back
1. (401) What is the relationship between current, voltage, and resistance in a circuit?
c. Current is directly proportional to the applied voltage and inversely proportional to the circuit resistance.
2. (401) If circuit resistance is increased from 4 ohms to 6 ohms and the applied voltage remains at 12 volts, the current
c. decreases to 2 amperes.
3. (401) If applied voltage of 48 volts produces a circuit current of 0.5 amperes, the circuit resistance is
c. 96 ohms.
4. (402) If the voltage across the load is 20 volts and the current through the load is 4 amperes, the power delivered to the load is
d. 80 watts.
5. (402) If the voltage developed across the load is 4 volts and the load resistance is 8 ohms, the power dissipated in the load is
b. 2 watts.
6. (402) Total electrical energy (W) expended in an electrical circuit can be defined as the product of
a. power and time.
7. (403) Four resistors of 20 ohms, 30 ohms, 50 ohms, and 60 ohms are connected in series across a battery rated at 110 volts. Determine the total resistance of the circuit.
c. 160 ohms.
8. (403) In a series circuit, R 1, R2, and R3 are 20 ohms each and the applied voltage is 180 volts. The current through R     2 is  
b. 3 amperes.
9. (403) R 1, R2, and R3 in a series circuit are 15, 30, and 45 ohms respectively, and the current through R     3 is 3 amperes. What is the applied voltage?  
c. 270 volts.
10. (403) Maximum power is transferred from a source to a load when the load resistance is equal to  
a. the internal resistance of the source.
11. (403) Most voltage measurements used to check proper circuit operation in electronic equipment are taken with respect to
d. ground.
12. (404) In a three-branch parallel circuit containing a 4-ohm, 5-ohm, and 6-ohm resistor, the current is
a. highest through the 4-ohm resistor.
13. (404) With 100 volts applied across ten 50-ohm resistances in parallel, the current through each resistance equals
a. 2 amps.
14. (405) The total resistance of 10 ohms, 20 ohms, and 25 ohms connected in parallel is
d. 10.52 ohms.
15. (405) What is the equivalent resistance of a 30-ohm and 20-ohm resistor connected in parallel with a source voltage of 24 volts and a total current of 2 amperes?
a. 12 ohms.
16. (405) If three resistors of 2, 4, and 6 ohms were connected in parallel, which resistor would dissipate the greatest power?
b. The 2-ohm resistor.
17. (406) What is the resistance of branch “a” (R 3, R4, R5 ) in figure T–1?  
b. 50 ohms.
18. (406) What is the resistance of branch “b” in figure T–1?
b. 50 ohms.
19. (406) What is the total resistance for the circuit in figure T–1?
b. 50 ohms.
20. (406) What is the total circuit current in figure T–1?
c. 5 amps.
21. (406) What is the voltage across R 1 in figure T–1?  
c. 125 volts.
22. (406) What is the current through branch “a” in figure T–1?
b. 2.50 amps.
23. (407) The sum of the power absorbed by all loads within a voltage divider is equal to the
a. power produced by the source.
24. (408) What are the two possible states of a Wheatstone bridge?
c. Balanced and unbalanced.
25. (408) What two parameters are measured by the galvonometer of a Wheatstone bridge?
d. Magnitude and direction of current flow.
26. (409) In a three-wire distribution system, an unbalanced situation is indicated by
d. current flow in the neutral wire.
27. (409) According to Kirchhoff’s law, which statement is correct as applied to three-wire distribution circuits?
a. Algebraic sum of all the voltages about a closed path is zero.
28. (409) What is the resistance and tolerance of a resistor with a color code of brown, black, red, and gold?
c. 1K ohm, ±5 percent.
29. (409) What is the resistance and tolerance of a resistor with a code of red, red, black, and silver?
a. 22 ohms, ±10 percent.
30. (410) An alternating-current generator converts
a. mechanical energy into electrical energy.
31. (410) An alternating-current generator made to deliver 60 hertz, with two field poles, needs an armature rotating at
d. 3,600 rpm.
32. (410) What is the frequency of an AC sine wave that repeats itself 500 times in 1/5 of a second?
d. 2,500 Hz.
33. (410) The root-mean-square value is known also as the
c. effective value.
34. (410) The most important value of a sine wave is
b. effective value.
35. (411) Inductance can be considered the property of a circuit that
a. opposes a change in current flow.
36. (411) When two coils are located so the flux from one coil links with the turns of the other coil, a change in flux in one coil causes an EMF to be induced in the other coil. This is called
b. mutual inductance.
37. (411) The phase relationship between current and voltage in a purely inductive circuit is when the voltage
a. leads current by 90°.
38. (412) If a transformer with a turns ratio of 1:4 has a primary voltage of 20 volts, the secondary voltage will be
c. 80 volts.
39. (412) An autotransformer possesses which characteristic?
a. Contains one winding.
40. (413) Capacitance is the property of an electrical device or circuit that
b. opposes any change of voltage.
41. (413) Which factor does not affect capacitance?  
b. Thickness of the plates.
42. (413) In a simple capacitor, the plate area is two square inches, the dielectric material is air, and the distance between the plates is 0.01 inch (0.254 mm). To increase the capacitance,
a. change the dielectric material from air to mica.
43. (413) When you select a capacitor for use in a circuit, its working voltage should be   at least  
d. 50 percent greater than the highest voltage to be applied to it.
44. (414) In a charged capacitor
b. one plate contains more free electrons.
45. (415) Connecting capacitors in parallel causes the plate area to
a. increase and capacitance to increase.
46. (415) Compute the total capacitance of a parallel circuit containing two capacitors: 5 μF and 10 μF.
c. 15 μF.
47. (416) Which capacitor type is polarized?
d. Electrolytic.
48. (416) When choosing a capacitor for a circuit the maximum safe voltage of a capacitor is the  
b. capacitor’s working voltage.
49. (416) Blocking direct current, filtering, and spark suppression are common applications of
d. capacitors.
50. (417) What is the opposition a coil offers to alternating current called and what is it measured in?
c. Inductive reactance, ohms.
x of y cards Next >|