A photosensitive metal is illuminated with monochromatic radiation of wavelength 400 nm. The wavelength is then reduced by 20%, while the metal and all other conditions remain unchanged. Experimentally, the stopping potential in the second case is found to be exactly twice the stopping potential in the first case. Take hc = 1240 eV·nm. If the threshold wavelength of the metal is approximately N nm, find N.
Physics · Photoelectric effect and dual nature of matter · question based on photoelectric effect
A photosensitive metal is illuminated with monochromatic radiation of wavelength 400 nm. The wavelength is then reduced by 20%, while the metal and all other conditions remain unchanged. Experimentally, the stopping potential in the second case is found to be exactly twice the stopping potential in the first case. Take hc = 1240 eV·nm. If the threshold wavelength of the metal is approximately N nm, find N.