Question

A wire of length `L metre ` , carrying a current `I `ampere is bent in the form of a circle . The magnitude of its magnetic moment is …………. ` MKS units ` .
A. `(IL)/(4pi)`
B. `(I^2L)/(4pi)`
C. `(IL^2)/(4pi)`
D. `(IL^2)/(pi)`

Answer 1

Correct Answer - C
`M= n I A =IA=I pi r^2`
Here `L= 2pi r rArr r=(L)/(2pi)`
`M=I pi ((L)/(2pi))^2=(IL^2)/(4pi)` .