ELA 125 test 3
Alternating current is defined as current which is periodically changing in ______, while continuously
changing in ______ - correct answer ✔✔Direction and Amplitude
The maximum value of an AC sine wave voltage is called the ____ value - correct answer ✔✔Peak
Unless otherwise specified, any values given for current or voltage in an ac circuit are assumed to be the
_____ or _____ value, which is equal to ______% of the peak value. - correct answer ✔✔Effective, RMS,
70
The number of complete cycles which are developed by alternator in a given unit of time is known as the
alternator's output - correct answer ✔✔Frequency
The amount of time needed to generate one cycle of AC is called the - correct answer ✔✔Period
How does the number of poles on the rotor of an alternator affect the output frequency of the unit -
correct answer ✔✔Directly proportional ( more poles, higher frequency at the same RPM)
How does the RPM of the rotor of an alternator affect the output frequency of the unit? - correct answer
✔✔Directly proportional (Higher RPM, higher frequency with the same number of poles)
What is the instantaneous value of voltage of a 200 volt peak sine wave at 30 degrees - correct answer
✔✔200 x Sin(30)= 100 volts
What is the instantaneous value of voltage of a 200 volt peak sine wave at 90 degrees - correct answer
✔✔200 x Sin(90) = 200 volts
What is resistance - correct answer ✔✔Is the opposition to current flow
