Magnetism Question 84

Question: The period of oscillation of a magnet in vibration magnetometer is 2 sec. The period of oscillation of a magnet whose magnetic moment is four times that of the first magnet is

[CPMT 1975, 77, 79, 89, 90; MP PMT 1986]

Options:

A) 1 sec

B) 4 sec

C) 8 sec

D) 0.5 sec

Show Answer

Answer:

Correct Answer: A

Solution:

$ \frac{T _{1}}{T _{2}}=\sqrt{\frac{M _{2}}{M _{1}}}=\sqrt{\frac{4M}{M}}=2\Rightarrow \frac{2}{T _{2}}=2 $
$ \Rightarrow T _{2}=1\sec $