An alternating current is represented by the equation I = I∫sinπt which of the following equation represents an alternating current of frequency and amplitude twice that of the above current ?
Correct answer: B. I = 2I∫Sin(2πt)
- A. I = 2I∫Sin(πt/2)
- B. I = 2I∫Sin(2πt)
- C. I = 2ISinπt
- D. I = I∫sin(2πt)
Explanation
The original current has amplitude I₀ and angular frequency π rad/s, so doubling both gives I = 2I₀ sin(2πt), with amplitude 2I₀ and frequency f = 2π/(2π) = 1 Hz. The likely wrong choice is c, which doubles the amplitude but leaves the frequency unchanged.
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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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