An electron of mass m and charge -e moves in circular orbit of radius r round the nucleus of charge +Ze in unielectron system. In CGS system the potential energy of electron is

Options

A. `(Z^(2)e^(2))/(r)`
B. `-(Ze^(2))/(r)`
C. `(Ze^(2))/(r)`
D. `(mv^(2))/(r)`

Answer

B

Explanation

(b) Potential energy = work done
` = int_(oo)^(r)-(Ze^(2) dr)/(r^(2))=-(Ze^(2))/(r)`