The maximum velocity of an electron emitted by light of wavelength `lambda` incident on the surface of a metal of work function `phi`, is
Where h = Planck's constant , m = mass of electron and c = speed of light.

Options

A. `[(2(hc+lamdaphi))/(mlamda)]^(1//2)`
B. `(2(hc-lamdaphi))/(mlamda)`
C. `[(2(hc-lamdaphi))/(mlamda)]^(1//2)`
D. `[(2(hlamda-phi))/m]^(1//2)`

Answer

C

Explanation

`1/2mv_m^2=(hc)/lamda-phi`
`impliesv_(m) =[(2(hc-lamdaphi))/(mlamda)]^(1/2)`