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A small signal voltage V(t)=V(0)sin omeg...

A small signal voltage `V(t)=V_(0)sin omegat` is applied across an ideal capacitor `C`:

A

over a full cycle the capacitor C does not consume any energy from the voltage source.

B

current I(t) is in phase with voltage V(t)

C

current `I(t)` leads voltage V(t) by `180^(@)`

D

current I(t), lags voltage V(t) by `90^(@)`.

Text Solution

Verified by Experts

The correct Answer is:
A
For an AC circuit containing capacitor only, the phase difference between current and voltage will be `pi/2` (i.e., `90^(@)`.
In this case current is ahead of voltage by `pi/2`.
Hence, power ini this case is given by
`P=Vicosphi`
where, `phi`= Phase difference between voltage and current)
`P=VIcos90^(@)`=0
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