NEET2010PhysicsMagnetic Effects of CurrentActual
A closely wound solenoid of 2000 turns and area of cross-section 1.5 10⁻⁴ ~m ^2 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 5 10⁻² ~T making an angle of 30^ with the axis of the solenoid. The torque on the solenoid will be
Options
- A3 10⁻³ ~N - m
- B1.5 10⁻³ ~N - m
- C1.5 10⁻² ~N -m
- D3 10⁻² ~N - m
Correct answer
C. 1.5 10⁻² ~N -m
Step-by-step solution
Given, N =2000, ~A =1.5 10⁻⁴ ~m ^2 i =2.0 AB =5 10⁻² ~T , and =30^ Torque, = NiBA aligned & =2000 2 5 10⁻² 1.5 10⁻⁴ 30^ & =2000 50 10⁻⁶ 1 2 & =1.5 10⁻² Nm aligned