Gyromagnetic ratio is the ratio of magnetic moment μl to the orbital angular momentum (l). Its numerical value for an electron is given by
The radius of the second Bohr orbit for hydrogen atom is: (Plank’s const. H = 6.6262 x10−34Js; mass of electron = 9.1091 x 10−31kg; charge of electron e = 1.60210 x 10−19C; permittivity of vaccum ϵ0=8.854185×10−12kg−1m−3A2)