## Tuesday, January 25, 2011

### Interference is in complete agreement to law of conservation of energy

Tilak gurjar posted;
"Interference is in complete agreement to law of conservation of energy. Comment"

If there were no interference, the resultant intensity at a point illuminated by two sources will be

I = I1+I2

Due to interference
$I_{max}=I_{1}+I_{2}+2\sqrt{I_{1}I_{2}}$
$I_{min}=I_{1}+I_{2}-2\sqrt{I_{1}I_{2}}$
$I_{average}=\frac{I_{max}+I_{min}}{2}=\frac{2I_{1}+2I_{2}}{2}=I_{1}+I_{2}$

This shows that energy is conserved even after interference. There is only a redistribution of energy. There is no loss or gain of energy