(a) Why photoelectric effect cannot be explained on the basis of wave nature of light? Give reasons.
(b) Write the basis features of photon picture of electromagnetic radiation on which Einstein’s photoelectric equation is based.a) Wave theory of light cannot explain the photoelectric effect because of the following reasons:
i) Wave nature does not explain the instantaneous ejection of photoelectrons.
ii) It does not explain to us the threshold frequency for a metal surface.
iii) Wave nature do not tell us, why kinetic energy of the emitted electrons is independent of the intensity of light and depends upon its frequency.
Basic features of photon picture of electromagnetic radiation on which Einstein’s photoelectric equation is based upon is:
b) Features of photons:
i) Photons are particles of light having energy, E =
and momentum, p = 
where h is Planck constant.ii) Photons travel with the speed of light in vacuum, independent of the frame of reference.
iii) Intensity of light depends on the number of photons crossing unit area in a unit time.
