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Flash and thunder are produced simultan...

Flash and thunder are produced simultaneously. But thunder is heard a few seconds after the flash is seen. Why?

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The light travels at the speed of `3xx 10^8 "ms"^(-1)` , which is very large in comparison to the speed of sound which travels at the rate of `330 "ms"^(1)` in the air. That is why lightning is seen earlier and thunder is heard later.
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