Practice Questions
A closely wound solenoid of 2000 turns and area of cross-section 1.5 × 10–4 m2 carries a current of 2.0 A. It is suspended through its centre and perpendicular to its length, allowing it to turn in a horizontal plane in a uniform magnetic field 1.5 × 10–2 T , making an angle of 30° with the axis of the solenoid. The torque on the solenoid will be?
1. 3 × 10–3 N-m
2. 4.5 × 10–3 N-m
3. 1.5 × 10–2 N-m
4. 3 × 10–2 N-m