The total energy of the electron revolving round the nucleus is

Options

A. `(1)/(2) (e^(2))/(r)`
B. `-(e^(2))/(r)`
C. `(me^(2))/(r)`
D. `-(1)/(2)(e^(2))/(r)`

Answer

D

Explanation

Total energy of a revolving electron is the sum of its kinetic and potential energy.
`= (e^(2))/(2r) + (-(e^(2))/(r)) = (e^(2) - 2e^(2))/(2r) = - (e^(2))/(2r)`