The photoelectric effect is the emission of electrons from a metal when light falls on it. The maximum kinetic energy of the electrons is the photon energy less the work function of the metal. A counter-electrode placed near the surface can pick up the photoelectric current.
a) The work function of copper is 4.65 eV. Calculate the maximum kinetic energy in eV of the electrons if a copper surface is illuminated with 200 nm UV light
b) If the counter-electrode is charged to +10 V, what will be the maximum kinetic energy of electrons arriving on it? What negative voltage would cut the photocurrent to zero?
