Discuss the behaviour of an inductor in d.c. and high frequency a.c. circuits.

Explanation

(i) For d.c., Frequency (v) = 0
and Capacitive reactance `X_C=1/(2pivC)=1/(2pi(0)C)=oo`
So capacitor offers infinite resistance and hence blocks d.c.
(ii) For a.c., Frequency (v) = finite value
and Capacitive reactance `(X_C) = 1/(2pivC)` = Small finite value
So capacitor offers small resistance and hence allows a.c. to pass through it.