# Fundamental Physics/Electricity/Electricity Source/PhotonElectric

## PhotonElectric Physics

According to Eistein, when one photon carries an energy hf interacts with a matter . Matter will absorb photon energy to the maximum at hfo after that the difference of energy (hf -hfo) will be used in releasing electron off matter into the surrounding

Mathematicaly, we can write

${\displaystyle hf=hf_{o}+{\frac {1}{2}}mv^{2}}$
${\displaystyle v={\sqrt {(hf-hf_{o}){\frac {2}{m}}}}}$

To release electron off matter, speed of electron must be greater than 0

${\displaystyle v>0}$ or ${\displaystyle f>f_{o}}$

From above, With

• ${\displaystyle hf=hf_{o}}$
${\displaystyle v={\sqrt {(hf_{o}-hf_{o}){\frac {2}{m}}}}=00}$
• ${\displaystyle hf=2hf_{o}}$
${\displaystyle v={\sqrt {(2hf_{o}-hf_{o}){\frac {2}{m}}}}}$
${\displaystyle v={\sqrt {hf_{o}{\frac {2}{m}}}}}$
• ${\displaystyle hf=(n+1)hf_{o}}$
${\displaystyle v={\sqrt {((n+1)hf_{o}-hf_{o}){\frac {2}{m}}}}}$
${\displaystyle v={\sqrt {nhf_{o}{\frac {2}{m}}}}}$