When an a.c. voltage is applied to a capacitor, no power is consumed because the current
Answer Details
When an AC (alternating current) voltage is applied to a capacitor, the current lags behind the voltage by 90 degrees. This means that when the voltage reaches its maximum value, the current is at its minimum value, and when the voltage is at its minimum value, the current is at its maximum value. However, even though the current is constantly changing, the net power consumed by the capacitor is zero. This is because the capacitor stores energy in its electric field when the voltage is increasing, and releases this stored energy when the voltage is decreasing. Therefore, over one complete cycle of the AC voltage, the energy stored in the capacitor is equal to the energy released, resulting in no net power consumption.