question_answer 40)

  Consider a beam of electrons (each electron with energy E0) incident on a metal surface kept in an evacuated chamber. Then (a) no electrons will be emitted as only photons can emit electrons (b) electrons can be emitted but all with an energy, E0 (c) electrons can be emitted with any energy, with a maximum of E0 - (  is the work function) (d) electrons can be emitted with any energy, with a maximum of E0

Answer:

  (d)When a beam of electrons of energy E0 is incident on a metal surface kept in an evacuated chamber, electrons can be emitted with maximum energy E0 (due to elastic collision ) and with any energy less than E0, when part of incident energy of electron is used in liberating the electron from the surface of metal.