A circular coil of `20turns` and radius `10cm` carries a current of `5A`. It is placed in a uniform magnetic field of `0*10T`. Find the torque acting on the coil when the magnetic field is applied (a) normal to the plane of the coil (b) in the plane of coil. Also find out the total force acting on the coil.

Options

A. 31.4 Nm
B. 3.14 Nm
C. 0.314 Nm
D. zero

Answer

D

Explanation

Torque acting on the coil is given by
`tau=BiBa= sin theta`
As, magnetic field is normal to plane of coil.
So, ` theta= 0^(@)`
`:. tau=0`