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Question
When a gun is fired at a distance, why is it that the flash is seen almost instantaneously while the sound is heard a little later?
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Solution
The reason is that the speed of light in air is 3 × 108 ms−1 which is much larger as compared to the speed of sound in air 3 × 102 ms−1. Hence light takes almost negligible time in comparison to sound in reaching us from the gun.
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What do you understand by the loudness of sound?
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(a)
(b)
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