A coil of resistance `400Omega` is placed in a magnetic field. If the magnetic flux `phi` (wb) linked with the coil varies with time `t` (sec) as `f=50t^(2)+4`, the current in the coil at `t=2` sec is

Options

A. 2A
B. 1A
C. 0.5 A
D. 0.1 A

Answer

C

Explanation

`|i|=(epsilon)/(R )=|-(dvarphi//dt)/(R )|=0.5A`