Using photon picture of light, show how Einstein's photoelectic equation can be established.

Explanation

Photolectons are emitted from plate P and are attracted towards C constituting photo
current. He found current is a function of potenial difference `V_(CP)` for constant frequency
and different intensity.
If `V_(CP)` is large and + ve , the current becomes constant.
The relation hv= `Phi_(0)+KE`
(i) Weve theoty states the KE of photoelectrons sholud increrase with intensity but
`K_(max) = eV_(0)` it is indepandent of intensity.
(ii) Weve theory state photoeletron should occure for any frequency of light, contrary,
photoemission is possible for threshold and higher frequencies.