Same current is flowing in two alternating circuits. The first circuit contains only inductances and the other contains only a capacitor, if the frequency of the e.m.f of AC is increased, the effect on the value of the current will be

Options

A. Decrease in both the circuits
B. Decrease in the first circuit and increase in the other
C. Increase in the first circuit and Decrease in the other
D. Increase in both the circuit

Answer

B

Explanation

For a.c. circuit containing only `L, X_(L) = omega L = 2 pi fL`
`:. i_(L) = V/(X_L) = V/(2 pifL)` thus, `i_(L) prop 1/f`
`:.` If f is increased, `i_(L)` will decrease.
For a capacitor, `X_(C) = 1/(2 pi fC)`
`:. i_(C) = (V_(0))/((1)/(2pifC)) = V_(0)(2pi fC)`
`:. i_(C) prop f :. i_(C)` will increase with increase in f.