If the electron of a hydrogen atom is present in the first orbit. The total energy of the electrons is

Options

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

Answer

c

Explanation

Kinetic energy =V` =1/2mv^(2)=1/2(e^(2))/(r^(2))(therefore mv^(2)=(e^(2)/r)`
Potential energy`(-e^(2))/r`
`therefore` Total energy of the electron =PE+KE
`(-e^(2))/r+1/2(e^(2))/(r)`
`(-e^(2))/(2r)`