If an orbital electron of the hydrogen atom jumps from the groud state to a higher energy state, its orbital value where its velcoity is reduced to half its initial value.. If the radius of the electron orbit in the ground state is `r`, then the radius of the new orbit would be:

Options

A. 3r
B. 4r
C. 5r
D. 2r

Answer

B

Explanation

For the electron `v prop 1/n`
`therefore v_2/v_1 = n_1/n_2 therefore 1/2 = 1/n therefore n_2 = 2`
But the radius `r_n prop n^2`
`therefore (r')/(r ) = (2)^2 =4 therefore r'=4r`