A magnet is suspended at an angle `60^(0)` in an external magnetic field of `5xx10^(-4)T`. What is the work done by the magnetic field in bringing it in its direction? `["The magnetic moment"=20A-m^(2)]`

Explanation

Work done by the magnetic field,
`W=MB(costheta_(1)-costheta_(2))`, Here `theta_(1)=60^(@)` and `theta_(2)=0^(@)`
`therefore W=20xx5xx10^(-4)[cos 60^(@)-cos0^(@)]`
`=10^(-2)[(1)/(2)-1]=-5xx10^(-3)J`.