Magnetism Question 132
Question: A bar magnet is oscillating in the earth’s magnetic field with time period T. If its mass is increased four times then its time period will be
[J & K CET 2004]
Options:
4 T
2 T
T
T/2
Show Answer
Answer:
Correct Answer: B
Solution:
$ T=2\pi \sqrt{\frac{I}{M\ B _{H}}} $ ; where $ I=\frac{m(L^{2}+b^{2})}{12} $ (m =Mass of magnet) $ \Rightarrow T\propto \sqrt{W}, $ If $ \text{w}\to $ four times then $ T\to $ Two times
 BETA
  BETA 
             
             
           
           
           
          