# Physics Course/Photo Electric Effect

## Photo Electric Effect

Photo Electric Effect is a physical effect observed when there is a Photonic Light shine on object has the capability to release Free Electron into the environment . ie the effect of Light generates Electricity

## Analysis

Energy of Photonic Light

E = hf

Maximum Energy absorb by object

E = hfo

Energy of Free Electron

${\displaystyle E={\frac {1}{2}}mv^{2}}$

From above

${\displaystyle hf=hf_{o}+{\frac {1}{2}}mv^{2}}$
${\displaystyle hf-hf_{o}={\frac {1}{2}}mv^{2}}$

In order to release a free electron the velocity of electron has to be greater than 0 . This only happens at

f > fo

and therefore

${\displaystyle v={\sqrt {{\frac {2h}{m}}(f-f_{o})}}}$

## Summary

Only Photonic Lights of energy hf that has frequency greater than the fresh hold frequency of the material are capable of generate Electricity. Photonic Lights that has capability of generating Electricity includes Visible Light, UV, X, Gamma.

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