question_answer

A coil of resistance 400Q is placed in a magnetic field. If the magnetic flux \[\phi \] (wb) linked with the coil varies with time t (sec) as\[\phi =50{{t}^{2}}+4\]. The current in the coil at t=2 sec is:

A) 0.5 A

B) 0.1 A

C) 2 A   

D) 1 A