25. (a) A circular coil of 20 turns and radius 10 cm is placed in a uniform magnetic field of 0.10 T normal to the plane of the coil. If the current in the coil is 5.0 A, what is the total torque on the coil,
As we know the torque on a current-carrying loop in a magnetic field is given by the following relation
It is clear that the torque, in this case, will be 0 as the area vector is along the magnetic field only.