The rartio `("in" S 1 units)` of magnetic dipole moment to that of the angular momentum of an electron of mass `m kg` and charge `e` coulomb in Bohr's orbit of hydrogen atom is

Options

A. `(e)/(2 m)`
B. `(e)/(m)`
C. `(2 e)/(m)`
D. none of these

Answer

A

Explanation

As magnetic moment , `mu_(B) = (1)/(2) e v r`
` L = m v r implies vr = (L)/(m)`
`:. mu_(B) = (1)/(2) (e L)/(m) implies (mu_(B))/(L) = (e)/(2 m)`