Tyndall effect

Tyndall effect

The Tyndall effect is an effect of light scattering by colloidal particles or particles in suspension. It is named after the 19th century Irish scientist John Tyndall. It is similar to Rayleigh scattering, in that the intensity of the scattered light depends on the fourth power of the frequency, so blue light is scattered more strongly than red light. An example in everyday life is the blue colour sometimes seen in the smoke emitted by motor bikes. The phenomenon is best explained by Mie theory as the particle size is much greater than the wavelength of light.

The basis for distinguishing between Tyndall and Rayleigh scattering is the intensity of the phenomenon. Colloidal particles are much larger than atoms or molecules. It follows from scattering theory that Tyndall scattering (by colloidal particles) is much more intense than Rayleigh scattering (by atoms or molecules). Tyndall scattering can be used to determine the size of colloidal particles. Tyndall scattering is also often used to describe light scattering by macroscopic particles such as dust in the air. However, this phenomenon is more like reflection, as the macroscopic particles become visible in the process.

When measuring Raman spectra of solutions, ultrafiltration may be needed to minimize interference by Tyndall scattering.

Prolonged and brilliantly coloured sunsets and twilights were frequently seen in London in the summer of 1815 due to Tyndall scattering of sunlight by ash particles in the upper atmosphere, produced by the earlier eruption of the volcano Tambora. Such a sunset may have been the inspiration for the brilliant and evocative sunset in the painting The Fighting Temeraire, though a similar effect could have been produced by Rayleigh scattering with exceptionally high atmospheric pressure.

See also

* [http://silver-lightning.com/tyndall/ demonstration]
* John Tyndall
* Rayleigh scattering
* Diffuse sky radiation ("Why is the sky blue?")
* Brownian motion, physical phenomenon where minute particles immersed in a fluid move about randomly.
* Crepuscular rays
* Volumetric lighting


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  • Tyndall effect — [tin′dəl] n. 〚after John Tyndall (1820 93), Brit physicist〛 Physics the scattering and polarization of a light beam by colloidal particles in a dispersed system * * * ▪ physics also called  Tyndall phenomenon        scattering of a beam of light… …   Universalium

  • Tyndall effect — n the scattering of a beam of light when passed through a medium containing small suspended particles (as smoky or mist laden air or colloidal solutions) called also Tyndall phenomenon * * * a strong beam of light passes through a true solution… …   Medical dictionary

  • Tyndall effect — [tin′dəl] n. [after John Tyndall (1820 93), Brit physicist] Physics the scattering and polarization of a light beam by colloidal particles in a dispersed system …   English World dictionary

  • Tyndall Effect —  Tyndall Effect  Эффект Тиндаля (рассеяние Тиндаля)   Рассеяние света при прохождении светового пучка через оптически неоднородную среду. Обычно наблюдается в виде светящегося конуса ( конус Тиндаля ), видимого на тёмном фоне. Характерен для в… …   Толковый англо-русский словарь по нанотехнологии. - М.

  • Tyndall effect — Tindalio reiškinys statusas T sritis fizika atitikmenys: angl. Faraday Tyndall effect; Tyndall effect vok. Faraday Tyndall Effekt, m; Tyndall Effekt, m rus. эффект Тиндаля, m; явление Фарадея Тиндаля, n pranc. effet Faraday Tyndall, m; effet… …   Fizikos terminų žodynas

  • Tyndall effect — noun the phenomenon in which light is scattered by very small particles in its path; it makes a beam of light visible; the scattered light is mainly blue • Hypernyms: ↑optical phenomenon * * * noun also tyndall phenomenon Usage: usually… …   Useful english dictionary

  • Tyndall effect — Tindalio reiškinys statusas T sritis chemija apibrėžtis Šviesos sklaida nuo tirpale ar ore esančių koloidinių dalelių. atitikmenys: angl. Tyndall effect rus. явление Тиндаля …   Chemijos terminų aiškinamasis žodynas

  • Tyndall effect — /ˈtɪndl əfɛkt/ (say tindl uhfekt) noun the scattering of light by particles of matter which makes a beam of light visible by illuminating the particles of dust floating in the air. {named after John Tyndall, 1820–93, Irish physicist} …  

  • Tyndall effect — noun The visible scattering of light along the path of a beam caused by discontinuities such as suspended particles …   Wiktionary

  • Faraday-Tyndall effect — Tindalio reiškinys statusas T sritis fizika atitikmenys: angl. Faraday Tyndall effect; Tyndall effect vok. Faraday Tyndall Effekt, m; Tyndall Effekt, m rus. эффект Тиндаля, m; явление Фарадея Тиндаля, n pranc. effet Faraday Tyndall, m; effet… …   Fizikos terminų žodynas

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