Physics Modern Physics Level: High School

Photoelectric Effect

The photoelectric effect is important for two reasons , firstly , it provides strong evidence for the particle nature of light , and secondly , it has a large number of practical applications .

a) Give one experimental observation coming from the study of the photoelectric effect that provides strong support for the particle theory of light .

b) State two practical applications of the photoelectric effect .

c) The work function of sodium is 2.46 eV .

i) Find the maximum frequency of radiation needed to eject photoelectrons from a sodium surface .

ii) If the sodium , surface is illuminated with radiation of wavelength 3.00 x 10^-7 metres , calculate the maximum kinetic energy of ejected photoelectrons .