A coil of inductance `300mh` and resistance `2Omega` is connected to a source of voltage `2V`. The current reaches half of its steady state value is

Options

A. `0.15s`
B. `0.3s`
C. `0.05s`
D. `0.1s`

Answer

D

Explanation

`i=i_(0)(1-e^(-Rt)/(L))impliesFor i=(i_(0))/(2),t=0.693(L)/(R )`
`impliest=0.693xx(300xx10^(-3))/(2)=0.1` sec