The ejection of the photoelectron from the silver metal in the photoelectric effect experiment can be stopped by applying the voltage of 0.35 V when the radiation 256.7 nm is used. Calculate the work function for silver metal.

The energy of the incident radiation, E = hν = hc/λ = 6.626×10⁻³⁴ × 3.0 × 10⁸ / 256.7 × 10⁻⁹ = 7.74 × 10⁻¹⁹ J. Convert the unit in eV. E = 7.74 × 10⁻¹⁹ / 1.602 × 10⁻¹⁹ = 4.83 eV. The potential energy is equal to 0.35 eV. The work function is 4.83 eV − 0.35 eV = 4.48 eV.