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Number of Results: 8 Search : Rayleigh

rayleigh rayleigh (#) Fr.: rayleigh A c.g.s. unit of light intensity used in astronomy and physics to measure
the brightness of the night sky, auroras, etc. One rayleigh (R) represents
the light intensity of one million photons of light emitted in all
directions per square centimeter of receiver per second; or, in SI
units, 795.775 x 10 In honor of the English mathematician and physicist Lord Rayleigh (1842-1919), surname of John William Strutt, Third Baron Rayleigh, whose research ranged over several fields of physics. |

Rayleigh line xatt-e Rayleigh Fr.: 1) droite de Rayleigh; 2) raie de Rayleigh 1) A straight line that connects the points corresponding to the initial and final states
on a graph of pressure versus specific volume for a substance subjected to a
→ |

Rayleigh number (Ra) adad-e Rayleigh Fr.: nombre de Rayleigh The ratio of the buoyancy force to the viscous force in a medium. This dimensionless number is used to estimate when convection commences in a fluid. It depends on the density and depth of the fluid, the coefficient of thermal expansion, the gravitational field, the temperature gradient, the thermal diffusivity, and the kinematic viscosity. Convection usually starts when Ra is 1000 or more, while heat transfer is entirely by conduction when Ra is less than 10. |

Rayleigh scattering parâkaneš-e Rayleigh Fr.: diffusion Rayleigh The scattering of light by → → |

Rayleigh's criterion sanjidâr-e Rayleigh Fr.: critère de Rayleigh A criterion for the instability of a basic swirling flow
with an arbitrary dependence of angular velocity Ω( |

Rayleigh-Jeans law qânun-e Rayleigh-Jeans(#) Fr.: loi de Rayleigh-Jeans A classical law approximately describing the intensity of radiation
emitted by a → |

Rayleigh-Jeans spectrum binâb-e Rayleigh-Jeans Fr.: spectre Rayleigh-Jeans The part of → |

Rayleigh-Taylor instability nâpâydâri-ye Rayleigh-Taylor Fr.: instabilité Rayleigh-Taylor A type of hydrodynamical instability between two fluids of different densities, which occurs when the heavy fluid lies above the lighter fluid in a gravitational field. More generally a material interface is said to be Rayleigh-Taylor unstable whenever the fluid acceleration has an opposite direction to the density gradient. → |