radiation pressure

American  

noun

Physics.

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

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radiation pressure Scientific  

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.

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Etymology

Origin of radiation pressure

First recorded in 1900–05

Example Sentences

Dust can be pushed outward by radiation pressure from the central star, swept up by planets or planetesimals, or spiral inward and fall into the star.

From Science Daily • Dec. 6, 2025

The second is that NGC 346 is taking more time to dissipate its protoplanetary disks because of radiation pressure being expelled from its stars.

From Salon • Dec. 21, 2024

“We see clear signs of outflowing material,” with radiation pressure sweeping out both hydrogen and dust, he says.

From Science Magazine • Mar. 27, 2023

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

From Scientific American • Aug. 23, 2022

“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 "Zero: The Biography of a Dangerous Idea" by Charles Seife