The time taken for an electron to complete one revolution in Bohr orbit of hydrogen atom is-

Options

A. `(4m^(2)pir^(2))/(n^(2)h^(2))`
B. `(n^(2)h^(2))/(4mr^(2))`
C. `(4pi^(2)mr^(2))/(nh)`
D. `(nh)/(4pi^(2)mr^(2))`

Answer

C

Explanation

According to Bohr's atomic model, `mvr=(nh)/(2pi)`
`v=(nh)/(2pimr),t=(2pir)/(v)=(2pirxx2pirm)/(nh)=(4pi^(2)mr^(2))/(nh)`