13 A student used two sources, A and B, of electromagnetic…

13 A student used twо sоurces, A аnd B, оf electromаgnetic rаdiation to investigate the photoelectric effect. Radiation from A has a photon energy of 2.0 eV.   (a) The radiation from B has a wavelength of 280 nm. Show that this radiation has a photon energy of about 4.4 eV. (4)       *(b) The student used the two sources of radiation to investigate the photoelectric effect for two different metals, copper and zinc.   The following statements were made by the student.   See addendum  Paragraph 13.1   Explain the conclusions that can be made from these statements. (6)   (Total for question 13 = 10 marks)