A circular coil of radius r is fromed by wire of length L.If current I is flowing through it then the magnetic moment Is proportional to

Options

A. `L^(2)`
B. L
C. `L^(3)`
D. `L^(1//2)`

Answer

A

Explanation

`L=2pir`
`therefore r=(L)/(2pi)`
`M=IA=Ipir^(2)`
`M=IA=Ipir^(2)`
`M=Ipi(L^(2))/(4pi)=(IL^(2))/(4pi)`
`Moo L^(2)`