Q. Write the expression for time period of oscillation of small compass needle in a uniform magnetic field and explain the terms. In this case if the magnitude of the magnetic field is reduced to 1/4th , how does the time period change?
Dear Student ,
Here is a link which will help you to solve this question with proper explanation .
https://www.meritnation.com/ask-answer/question/a-small-compas-needle-of-magnetic-moment-m-and-moment-of/atoms/3605732
Now when the magnetic field is 1/4 th of its initial value then the time period will be 2 times the initial time period .
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