A light source of wavelength `lambda` illuminates a metal and ejects photo-electrons with `(K.E.)_(max) =1.eV` Another light source of wavelength `(lambda)/(3)`, ejects photo-electrons from same metal with `(K.E.)_(max) = 4eV` Find the value of work function?

Options

A. `1 eV`
B. `2 eV`
C. `0.5 eV`
D. none of these

Answer

C

Explanation

`T_(1)/T_(2)=n_(1)^(3)/n_(2)^(3)=1^(3)/2^(3)=1/8`
`:' (T=(2pir)/V)` so, `T prop n^(3)/Z^(2)`