Derive formula for force on a plate of mass m if a light of intensity I is illuminated on it within area A, wavelength is lamda . derive formula of force for 4 following cases

Asked by advait2163 | 29th Mar, 2012, 08:51: PM

Expert Answer:

1.when the light is absorbed totally,the momentum of light is totally transfered in elestic collision.
initial momentum associated with light=p=U/c
So change in momentum/time hence force=-U/c
2) When the light is reflected totally,
change in momentum/time=-p-p=-2p=-2U/c, hence force.

Answered by  | 8th May, 2013, 10:53: AM
