A circular coil has moment of inertia `"0.8 kg m"^(2)` around any diameter and is carrying current to produce a magnetic moment of `20Am^(2)`. The coil is kept initially in a vertical position and it can rotate freely around a horizontal diameter. When a uniform magnetic field of 4 T is applied along the vertical, it starts rotating around its horizontal diameter. The angular speed the coil acquires after rotating by `60^(@)` will be :

Options

A. `10pi" rad s"^(-1)`
B. `20" rad s"^(-1)`
C. `"10 rad s"^(-1)`
D. `20pi" rad s"^(-1)`