MHT CET Medical202622 April 2026Evening ShiftPhysicsMagnetic Effects of CurrentActual
A closely wound solenoid of 1000 turns and area of cross-section 2 10⁻⁴ m ^2 carries a current of 2 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 5 10⁻² T making an angle of 60^ with the axis of solenoid. The torque on a solenoid will be nearly ( 60^ = 3 2 )
Options
- A1.7 10⁻² Nm
- B1.5 10⁻² Nm
- C3.4 10⁻² Nm
- D2 10⁻² Nm
Correct answer
A. 1.7 10⁻² Nm
Step-by-step solution
The magnetic moment of the solenoid is given by M = NIA Substituting the given values: M = 1000 2 2 10⁻⁴ = 0.4 A m ^2 The torque acting on the solenoid in a uniform magnetic field is given by = MB Substituting the values: = 0.4 5 10⁻² 60^ = 2 10⁻² 3 2 = 3 10⁻² 1.732 10⁻² Nm Answer: 1.7 10⁻² Nm