Questions on the Photoelectric Effect

Q5. In the apparatus shown, monochromatic ultraviolet radiation is incident on the surface of metal X. Photoelectrons are emitted from X and are collected at electrode Y.

(a) Calculate the work function of X, given that each photon in the incident radiation has 3.2 × 10–19 J of energy. The maximum kinetic energy possessed by a single photoelectron is 2.1 × 10–19 J.

(3 marks)

(b) The source of the incident radiation is replaced with a new source. The wavelength of the radiation from the new source is half the wavelength of the original radiation. Calculate the maximum kinetic energy of the emitted photoelectrons.

(3 marks)

(Total 6 marks)