For silver metal, threshold frequency for emission of photoelectron is $1.13\times {10}^{17}{\mathrm{s}}^{-1}$. The kinetic energy of electrons emitted when silver is irradiated with wavelength 1.5 nm is

Energy carried by one photon of wavelength 1.5 nm is

${\mathrm{E}}_1=\frac{\mathrm{hc}}{\mathrm{\lambda }}=\frac{\left(6.626\times {10}^{-34}\mathrm{Js}\right)\left(3\times {10}^8{\mathrm{ms}}^{-1}\right)}{\left(1.5\times {10}^{-9}\mathrm{m}\right)}=1.325\times {10}^{-16}\mathrm{J}$

Energy carried by one photon of frequency $1.13\times {10}^{17}{\mathrm{s}}^{-1}$ is

${\mathrm{E}}_2=\mathrm{h\nu }=\left(6.626\times {10}^{-34}\mathrm{Js}\right)\left(1.13\times {10}^{17}{\mathrm{s}}^{-1}\right)=7.49\times {10}^{-17}\mathrm{J}$

Kinetic energy of a single electron is

$\mathrm{\Delta E}={\mathrm{E}}_1-{\mathrm{E}}_2=(13.25-7.49)\times {10}^{-17}\mathrm{J}=5.76\times {10}^{-17}\mathrm{J}$