An alternating current of the r.m.s value of 4.0 A and frequency 50Hz flows in a circuit containing a 10Ω resistor. The peak current is then ?
Correct answer: D. 5.66A
- A. 20A
- B. 20.66A
- C. 6.66A
- D. 5.66A
Explanation
For a sinusoidal current, Ipeak = √2 Irms = 1.414 x 4.0 A = 5.66 A. The frequency of 50 Hz and resistance of 10 Ω are not needed to find the peak current. The likely wrong choice is a, caused by confusing peak current with a value obtained from the resistor or by using an incorrect RMS conversion.
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About Phase of Alternating Current
Phase describes the position of an alternating voltage or current within its cycle and the phase difference between two sinusoidal quantities. The topic covers in phase signals, phase angle and lead or lag in resistive, inductive and capacitive circuits, rather than the amplitude or frequency of the supply.
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