A closely wound solenoid of 2000 turns and area of cross-section 1.6 × 10 –4 m2 , carrying a current of 4.0 A, is suspended through its centre allowing it to turn in a horizontal plane.
(i) What is the magnetic moment associated with the solenoid?
(ii) What is the force and torque on the solenoid if a uniform horizontal magnetic field of
7.5 × 10–2 T is set up at an angle of 30° with the axis of the solenoid?