A wire of length L metre carrying a current I ampere is bent in the form of a circle. Its magnitude of magnetic moment will be
Answer & explanation
Correct answer: option 4
The correct answer is Option 4: $IL^2/4π$
$\text{Length of loop } L = 2\pi r$
$\Rightarrow r = \frac{L}{2\pi}$
$\text{magnetic Moment } M = IA = I\pi r^2 = I \pi \frac{L^2}{4\pi^2}$
$ M =\frac{IL^2}{4\pi}$