What is radiation pressure?
(N/A) Radiation pressure is the mechanical pressure exerted upon any surface due to the exchange of momentum between the electromagnetic field and the surface.
When electromagnetic waves (such as light) strike a surface,they transfer momentum to it.
According to the theory of electromagnetism,if a surface completely absorbs an electromagnetic wave of energy $U$,the momentum transferred to the surface is $p = U/c$,where $c$ is the speed of light.
If the surface completely reflects the wave,the momentum transferred is $p = 2U/c$.
This transfer of momentum results in a force,and the force per unit area is defined as radiation pressure.
When electromagnetic waves (such as light) strike a surface,they transfer momentum to it.
According to the theory of electromagnetism,if a surface completely absorbs an electromagnetic wave of energy $U$,the momentum transferred to the surface is $p = U/c$,where $c$ is the speed of light.
If the surface completely reflects the wave,the momentum transferred is $p = 2U/c$.
This transfer of momentum results in a force,and the force per unit area is defined as radiation pressure.
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