Question
Consider a beam of monochromatic light with intensity $I$ incident on a perfectly absorbing surface oriented perpendicular to the beam. Use the photon concept to show that the radiation pressure exerted by the light on the surface is given by $I / c$ .
Step 1
The radiation pressure is the force acting on the surface due to the light. We know that light carries momentum, so it can exert a force. The pressure is then given by the force over the area, or $P = F/A$. Show more…
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