1

a. State three aspects of the photoelectric effect that cannot be explained by the wave theory of light. For each, outline how the photon theory provides an explanation.

b Light of wavelength 2.08 10^-7 m falls on a photo-surface. The stopping voltage is 1.40 V

i) Outline what is meant by stopping voltage.

ii) Calculate the largest wavelength of light that will result in emission of electrons from this photo-surface