Correct Answer - C
The kinetic energy of the electron in hydrogen atom are
`K=(1)/(2)mv^2=(e^2)/(8piepsilon_0r)[becausev^2=(e^2)/(4piepsilon_0mr)]`
electrostatic potential energy,
`U=(-e^2)/(4piepsilon_0r)`
The total energy E of the electron in a hydrogen atom is `E=K+U,E=(e^2)/(8piepsilon_0r)+((-e^2)/(4piepsilon_0r))=-(e^2)/(8piepsilon_0r)`
here negative sign shows that electron is bound to the nucleus.
