Problem 2. A sodium photoelectric surface with work function 2.3eV is illuminated and emits electrons. The electrons travel toward a negatively charged cathode and complete a circuit. The potential difference supplied by the power supply is increased, and when it reaches 4.5V, no electrons reach the cathode. a) For the electrons emitted from the sodium surface, calculate the following. i. The maximum kinetic energy ii. The electron speed at this maximum kinetic energy b) Calculate the wavelength of the radiation that is incident on the sodium surface. c) Calculate the minimum frequency of light that will cause photoemission from this sodium surface.