Wavelength of electron waves in two Bohr orbits is in ratio3:5 the ratio of kinetic energy of electron is 25 : x, hence x is :

Options

A. `25:9`
B. `5:3`
C. `9:25`
D. `3:5`

Answer

A

Explanation

`K.E. prop v^(2)` and `lambda prop 1//v`
`:. lambda^(2) prop 1//K.E.`
`:. (lambda_(1)^(2))/(lambda_(2)^(2)) = ((K.E.)_(2))/((K.E.)_(1))`
`((K.E.)_(1))/((K.E.)_(2)) = ((5)^(2))/((3)^(2)) = (25)/(9)`