Describe briefly how wave theory of …

Acc to wave theory, light is an em wave consisting of electric and magnetic fields with continuous distribution of energy over the region over which the wave extends. This wave picture of light could not explain the basic features of light as given below. 1. Acc to wave theory, when a wavefront of light strikes the metal surface, the free electrons at the sirface absorb the radiant energy continuously. Greater the intensity of incident radiation, greater are the amplitude of electric and magnetic fields and greater is the energy density of wave. Hence higher intensity should liberate photo electrons with greater kinetic energy. But this is contrary to the experimental result that the maximum kinetic ecmnergy of the photoelectorns does not depend on intensity of incident radiation. 2. No matter what the frequency of incident radiation is, a light wave of sufficient intensity (over a sufficient time) should be able to impart enough energy required to ehect the electron from the metal surface. Thus wave theory fails to explain the existence of threshold frequency. 3. The energy of light wave is smoothly and evenly distributed across its advancing wavefront. Each electron intercepts an insignificantly small amount of this energy and so it should require a finite time to escape from the metal surface. But actually the emission is almost instantaneous.