2015-PHYSICS-EN.pdf - Foxit PDF Reader X File Home Comment View Form Protect Foxit eSign Share Help Q Tell me... Q Find . . . AB Hand Select Read Reflow Reverse Night Text Rotate AutoScroll Assistant Read Word View Mode View Mode Viewer View Count Setting Edit PDF like a Start 2013-PHYSICS-EN.pdf 2015-PHYSICS-EN.pdf X 2015_PHYSICS_SOLUT... word processor coated electrode. W There is no potential difference between the electrodes. The maximum speed of these electrons is Vmax = 5.17 x 10' m-s-1. iii. Determine the wavelength of these photons in vacuum. 4 marks Photons of wavelength 450 nm in the vacuum illuminate a photoelectric cell. Its cathode is covered with cesium. The power of the light illuminating the cathode is P = 5.00 x 10" W. The number of electrons per second emitted by the cathode is 0.10 % of the number of photons per second illuminating the cathode of the cell. iv. Calculate the saturation current of the cell in this situation. 4 marks Given: elementary charge e = 1.60x10-19 C speed of light in a vacuum c= 3.00x10 m s-1 mass of the electron me = 9.11x10-> kg the Planck constant h =6.63 x 10 34 kg m s-] work function of cesium 1.94 eV work function of zinc 4.31 ev work function of platinum 6.35 eV