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Question
When an AC voltage of 220 V is applied to the capacitor C ______.
- the maximum voltage between plates is 220 V.
- the current is in phase with the applied voltage.
- the charge on the plates is in phase with the applied voltage.
- power delivered to the capacitor is zero.
Options
b and c
a and d
b and d
c and d
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Solution
c and d
Explanation:
If the alternating voltage is applied to the capacitor, the plate connected to the positive terminal of the source will be at a higher potential and the plate connected to the negative terminal of the source will be at a lower potential. So the plate's capacitor is charged.
Power applied to circuit is `P_(av) = V_(rms) I_(rms) cos phi`
`phi` = 90° for pure capacitor circuit
∴ Pav = Vrms Irms cos 90° = 0.
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