AP EAMCET2007PhysicsMagnetic Properties of Matter
A bar-magnet of moment of inertia 49 10⁻² ~kg - m ^2 vibrates in a magnetic field of induction 0.5 10⁻⁴ ~T . The time period of vibration is 8.8 ~s . The magnetic moment of the bar magnet is
Options
- A350 ~A - m ^2
- B490 ~A - m ^2
- C3300 ~A - m ^2
- D5000 A-m ^2
Correct answer
D. 5000 A-m ^2
Step-by-step solution
Time period of magnet is aligned T & =2 I M H or M & = 4 ^2 I T^2 H or M & = 4 (3.14)^2 49 10⁻² (8.8)^2 0.5 10⁻⁴ or M & =5000 ~A - mf ^2 aligned