stokes' law

noun

Usage: usually capitalized S

Etymology: after Sir George G. Stokes

1. : a law in physics: the frequency of luminescence excited by radiation does not exceed that of the exciting radiation

2. : a law in physics: the force required to move a sphere through a given viscous fluid at a low uniform velocity is directly proportional to the velocity and radius of the sphere

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Physics.

1. the law that the force that retards a sphere moving through a viscous fluid is directly proportional to the velocity of the sphere, the radius of the sphere, and the viscosity of the fluid.

2. the law that the frequency of luminescence induced by radiation is usually less than the frequency of the radiation.

[named after Sir G. STOKES]

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Stokes' law noun

1. Either of two laws in physics: (1) the frequency of luminescence excited by radiation is usually less than the frequency of the radiation which excites it

2. (2) the force needed to move a sphere through a viscous fluid is directly proportional to the velocity of the sphere, its radius, and the viscosity of the fluid

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Main Entry: ↑stokes

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Stokes' law «stohks»,

Physics. the law that the frequency of luminescence excited by radiation is usually not higher than the frequency of the exciting radiation.

╂[< Sir George Stokes, 1819-1903, a British mathematician and physicist]

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[stōks]

Physics

1) a law stating that in fluorescence the wavelength of the emitted radiation is longer than that of the radiation causing it. This is not true in all cases

2) an expression describing the resisting force on a particle moving through a viscous fluid and showing that a maximum velocity is reached in such cases, e.g., for an object falling under gravity through a fluid

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Origin:

late 19th cent.: named after Sir George Stokes (1819 - 1903), British physicist