If photons hit one Crookes radiometer (or a solar sail, or similar reflecting and movable object) and are reflected (making it move) would the photons lose any momentum?
If not, where does the kinetic energy won by the radiometer comes from?
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Sign up to join this communityIf photons hit one Crookes radiometer (or a solar sail, or similar reflecting and movable object) and are reflected (making it move) would the photons lose any momentum?
If not, where does the kinetic energy won by the radiometer comes from?
The Crookes radiometer does not use radiation pressure (transfer of momentum from photons) as an operating principle. The vanes are suspended in only partial vacuum and the blackened sides are heated by the incident light which causes a force due to the momentum transfer to impinging and then "reflected" gas molecules.