A 100 turns closely wound circular coil of radius 10 cm carries a current of 3.2 A.
What is the magnetic moment of this arrangement?

Explanation

Magnetic moment,
`M=NiA`
`=Ni xx pi r^(2)`
`=100 xx 3.2 xx 3.14 xx (10 xx 10^(-2))^(2)`
`=10.048 "A-m"^(2)`