Thunder

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Thunder is the sound of the shockwave caused when lightning instantly heats the air around it to up to 30 000 °C (54 000 °F). That super-heated air expands rapidly, then contracts as it cools. The rapid expansion/contraction generates sound waves, making the sound that is called "thunder."

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Etymology

The d in thunder is epenthetic, and is not found in Modern Dutch donder, from earlier d-less Old English þunor, Middle Dutch donre, together with Old Norse þorr, Old Frisian þuner, Old High German donar descended from Proto-Germanic *þunraz, built on a PIE stem *Template:PIE also found in Sanskrit Template:IAST "thundering", Latin tonare "to thunder" (see also tornado).

Calculating distance

Since sound and light travel at different speeds through the atmosphere, one can estimate how far away the bolt of lightning is by timing the interval between seeing the flash and hearing the thunder. The speed of sound in air is approximately 332 m/s (742.6 mph). The speed of light is so fast that it can be ignored in this calculation. Therefore, the lightning is approximately one kilometer distant for every 3 seconds (or one mile for every 5 seconds).

List of thunder gods

Polytheistic peoples in areas with much thunder, or areas where thunder precedes drought-breaking rain, may postulate a thunder god.

Ancient Near East

Eurasian

East Asia

Americas

Africa

South Pacific

See also: Category:Thunder gods

See also

External links

de:Donner eo:Tondro es:Trueno fr:Tonnerre he:רעם id:Petir it:Tuono ja:雷 ko:천둥 nl:Donder pl:Grzmot ru:Гром simple:Thunder sk:Hrom sv:Åska vi:Sấm yi:דונער zh:雷