The potential energy of the orbital electron in the ground state of hydrogen atom is -E What is its kinetic energy ?-

Options

A. `(E)/(4)`
B. `(E)/(2)`
C. 2E
D. 4E

Answer

B

Explanation

For ground state of `H_(2)`
`(mv^(2))/(r)=(ke^(2))/(r^(2)) rArr (1)/(2) mv^(2)=(ke^(2))/(2r)...(1)`
Potential energy `=-(ke^(2))/(r)....(2)`
Say E is potential energy then `E=-(ke^(2))/(r)`
`:.` Kinetic energy `=-(ke^(2))/(r)=(1)/(2)(-(ke^(2))/(r))`
`:.` Kinetic energy `=(E)/(2)`