Physics

Problem

Monochromatic light of wavelength

400\,\text{nm}

is incident on a potassium surface whose work function is

2.2\,\text{eV}

. Determine the stopping potential. \newline (Given

h=6.63\times10^{-34}\,\text{J s}

c=3.0\times10^{8}\,\text{m s}^{-1}

e=1.6\times10^{-19}\,\text{C}

)