How does a Radiometer Work?

Radiometers are simply a way using light as an energy source. It has two surfaces on vanes inside a glass tube or container, one side is shiny and the other is blackened. When the light hits the shiny side it reflects it and on the blackened side it absorbs the light which in turn gives off heat enough to track how much light there is. The vanes are the gauge the pressure of the light. When there is enough light, energy from the light turns the vanes! Radiometers give us the particle like nature of light. It produces a helium type gas. Other names for radiometers are light mill or Crookes Radiometer. For more information see here: