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प्रश्न
Flash and thunder are produced simultaneously. But thunder is heard a few seconds after the flash is seen, why?
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उत्तर
The speed of light (c) is greater than the speed of sound (v) by a factor of 106 as
`c/v` = `(3 xx 10^8 m s^(-1))/(340 m s^(-1)) ≈ 10^6`
As a result, even though both are produced at the same time, the flash of light is viewed before the thunder of sound.
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