Derive an expression for the magnetic moment `(vec mu)` of an electron revolving around the nucleus in termsof its angular momentum `(vecl)`. What is the direction of the magnetic moment of the electron with respect to its angular momentum?

Explanation

We have `mu=iA(ev)/(2pir)xxpir^(2)=(evr)/(2)`
`"Since "l=mvr`
`"or "vr=(1)/(m)" "therefore(vec mu)=-(evecl)/(2m)" "[therefore" electron has a negative charge"]`
The direction of `(vec mu)` is opposite to that of `vecl`, because of the negative charge of the electron.