The inductance of a coil in which a current of 0.2 A is increasing at the rate of 0.5 A/s represents a power flow of 0.5 W is

Options

A. 2 H
B. 5 H
C. 10 H
D. 20 H

Answer

B

Explanation

Energy stored in inductance
`U=(1)/(2)Ll^(2)`
Power `P=(dU)/(dt)=(d)/(dt)((1)/(2)Ll^(2))=Ll(dl)/(dt)`
`thereforeL=(P)/(l(dt)/(dt))=(0.5)/(0.2xx0.5)=5H`