Question

A wire of length 2 m carrier of lamp is bend to form a circle. The magnetic moment of a coil is :-

Options

• `2pi`

• `pi/2`

• `pi/4`

• `1/pi`

Answer 1

`1/pi`

Explanation:

Here 2πr = 2 or r = 1/πm

Magnetic moment , M = 1A = 1πr²

= `1 xx pi xx (1/pi)^2 = 1/pi AM^2`