Solution to task 556 from Chertov´s for extramural stud

Solution to task 556 from Chertov´s for extramural stud

556. A beam of ultraviolet radiation (λ = 0.25 µm) is directed to the metal plate. The phototech stops at the minimum retarding potential difference Umin = 0.96 V. Determine the work function A of electrons from the metal.