A coil of resistance $400\Omega$ is placed in a magnetic filed. if the magnetic flux $\phi$ (wb) linked with the coil varies with times t(sec) as <br> $\phi = 50 t^2 + 4.$ . The current is the coil at t = 2 sec is

Question

( A ) 0.1 A
( B ) 2A
( C ) 0.5A
( D ) 1A