radiation pressure

noun

, Physics.

1. the pressure exerted on a surface by electromagnetic radiation or by sound waves.

radiation pressure

1. Force per unit area exerted by waves or particles of radiation, especially photons. Though photons have no mass, they do have momentum, and can transfer that momentum to other particles upon impact. The amount of pressure exerted by a given amount of radiation depends on whether the radiation is absorbed or reflected. Radiation pressure is responsible for the Casimir effect; solar radiation pressure is exploited in the design of solar sails .

Word History and Origins

Origin of radiation pressure¹

First recorded in 1900–05

Example Sentences

These are more powerful than run-of-the-mill supernovae, which occur when a star runs out of fuel and implodes with a sudden loss of radiation pressure akin to demolishing the supports holding up a roof.

From Scientific American

During the star-forming phases, the radiation pressure from the stars would blast out dust, making the galaxies appear bright and blue.

From Science Magazine

Solar radiation pressure is exceedingly weak, however, which is why practical solar sails must be so large.

From Scientific American

“I’m making an analogy to the Casimir effect, where you can push plates together with a noticeable radiation pressure from the vacuum,’’ he says.

From Literature

Spacecraft powered by novel propulsion methods, such as light sails accelerated by a laser beam from Earth or by solar radiation pressure, are another option, but they involve difficulties of their own.

From Scientific American