The time period of a bar magnet suspended horizontally in th... | PHYSICS - THE EARTH'S MAGNETISM | SolveeIt | Solveeit

Today, August 19

Question

The time period of a bar magnet suspended horizontally in the earth's magnetic field and allowed to oscillate

A

Is directly proportional to the square root of its mass

B

Is directly proportional to its pole strength

C

Is inversely proportional to its magnetic moment

D

Decreases if the length increases but pole strength remains same

Answer

Is directly proportional to the square root of its mass

Explanation

Solution

$T = 2 \pi \sqrt { \frac { I } { M B _ { H } } }$ and $I = \frac { \mathrm { w } \left( l ^ { 2 } + b ^ { 2 } \right) } { 12 } ; \therefore T \propto \sqrt { \mathrm { w } }$

(w = Mass of the magnet)