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Flash ans thunder are produced simultane...

Flash ans thunder are produced simultaneously. But thunder is heard a few seconds after the flash is seen, why ?

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The speed of light (c) is greater than the speed of sound (v) by a factor of `10^6 "as" c//v = (3 xx 10^8 m//s)/(340 m//s) ~= 10^6`.
Thus, the flash of light is seen earlier than the thunder of sound even though both are produced simultaneously.
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