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.
Given:
Work Function of metal, W = 037eV
Wavelength, λ = 256.7 nm
From the Law of conservation of energy, the energy of an incident photon [E] is equal to the sum of the work function [W] of radiation and its kinetic energy [K.E] i.e.,
Energy of incident radiation [E] = hc/λ = [6.626× 10-34] [3× 108] [256.7× 10-9]
= 7.74× 10-19 J
Since the potential applied gives the kinetic energy to the radiation, therefore K.E of the electron = 0.35Ev
Therefore, work function = 4.83 – 0.35
= 4.48 eV
Therefore, the work function of metal is 4.48 eV