MHT CET202019 Oct 2020Morning ShiftPhysicsMagnetic Properties of MatterActual
A bar magnet is held perpendicular to a uniform magnetic field. The couple acting on the magnet is to be halved by rotating it. Through what angle it should be rotated? [ ( 2 )=1 ]
Options
- A⁻¹(0 8660)
- B⁻¹(0 7071)
- C⁻¹(1)
- D⁻¹(0 5)
Correct answer
D. ⁻¹(0 5)
Step-by-step solution
(D) T=M B When = 2 , ~T = MB 2 = MB Let T^ = T 2 =M B ^ = M B 2 =M B ^ ^ = 1 2 =0.5 ^ = ⁻¹ 0.5