question_answer 16)

Obtain the answers to (a) and (b) in Exercise 7.15 if the circuit is connected to a 110 V, 12 kHz supply. Hence, explain the statement that a capacitor is a conductor at very high frequencies. Compare this behaviour with that of a capacitor in a dc circuit after the steady state.  

Answer:

(a)                                                 (b)                                                 or is nearly zero at high frequency. In part (a) C term is negligible at high frequency so it acts like a resistor. For a steady d. c. we have and so it acts like an open circuit for steady d.c.