Write Einsteins's equation of photoelectric effect. Give Einstens explanation of photoelectric effect.

Explanation

Einstein equation of photoelectric effect is given by
`K_(max) = hv -phi`
Einstein.s explanataion of photoelectric effect
1 . According to Einstein.s theory , the basic elementry process involved in photoelectric effect is the absorption of light quantum by an electron . This process is instantneous Thus , irrespective of the intesity , photoelectric effect is instaneous.
(2) According to Einstien.s equation `K_(max) = hv -phi_(0) `. K depends linarly on v as `phi` is a constant for a given metal. Also `K_(max)` is independent of intensity of radiation. Above concepts are in goods agreement with experimental observation. This is due to fact that according to Einstein theory, photoelectric effect arises from the absorption of a single quantum of radiation by a single electron.
3.`K_(max)` is always non- negative.
Photoelectric emission is possible only if `hv > phi_(0)` where `v_(a)` where v-(0) = (phi_(0))/(h)`
thus , there exists a threshold frequency for the metal surface , below which no photoelectric emission possible no matter how intense the incident radiation may be or how long it falls in the surface .
4. intensive of radiation is proportional to the number of energy quanta per unit area per unit time . The greater the number of energy . Hence the number of electrons coming out of the metal is also higher . This expakins why for `V > V_(0)` photo electric current is propotional to intensity .