Write Einstein’s photoelectric equation. State clearly how this equation is obtained using the photon picture of electromagnetic radiation.
Write the three salient features observed in photoelectric effect which can be explained using this equation.Einstein’s photo electric equation is given by,
where, h is planck’s constant, 
is the frequency and 
is the work function.
The energy (h
) carried by a photon of frequency is absorbed by electrons on the surface to
i) overcome the work function of metal .
ii) impart maximum K.E. to the emitted electron (Kmax.)
Salient features observed in photoelectric effect are:
i) The stopping potential and maximum kinetic energy of emitted electrons varies linearly with the frequency of incident radiation.
ii) Photoelectric emission is possible when, 
where, 
is the cut-off frequency.
