The self inductance of the motor of an electric fan is 10H. In order to impart maximum power at 50 Hz, it should be connected to a capacitance of

Options

A. `4 mu F`
B. `2 mu F`
C. `8 mu F`
D. `1 mu F`

Answer

D

Explanation

For maximum power, `L omega = 1/(C omega)`
`:. C = 1/(L omega^(2)) = (1)/(L cdot 4 pi^(2)n^(2))`
`= (1)/(10 xx 4 xx 10 xx 2500) [pi^(2)-:10 and n=50]`
`:. C = 1/(10^6) = 10^(-6)F = 1 mu F`.