The relation between the stopping potential and the frequency of the incident light is given by
eV0=hν−ϕ...(1)
When V0=0,
ϕ=hν...(2)
Substitute the value of the frequency corresponding to zero stopping potential into equation (2) to calculate the required work function of the material.
ϕ==1.6×10−19J/eV6.626×10−34J⋅s×5×1014Hz166.626×5≈2.07eV
