question_answer

A diode is connected to \[\mathbf{220}\text{ }\mathbf{V}\text{ }\left( \mathbf{rms} \right)\] a .c. in series with a capacitor, as shown below. What is the voltage \[V\] across the capacitor?              

Answer:

                    During the positive half cycle of input a. c. (when the diode gets forward biased), the capacitor charges itself to the peak value of the supply voltage. Therefore, the voltage across the capacitor is \[V={{V}_{0}}=\sqrt{2}{{V}_{rms}}=\sqrt{2}\times 220=\mathbf{311}\mathbf{.1V}\]