Question

Two bar magnets are placed together suspended in the uniform magnetic field vibrates with a time period is 3 second. If one magnet is reversed, the combination takes 4s for one vibration . The ratio of their mgnetic moments is

• A. 3 : 1
• B. 5 : 18
• C. 18 : 5
• D. 25 : 7

Answer 1

Answer: (D)

$T\propto \sqrt{\frac{I}{M}}$