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CBSE Class 9 Answered

If sound does not travel on moon, it means it is a vaccum. but it's not true. Please explain.
Asked by | 04 Mar, 2012, 06:11: PM
answered-by-expert Expert Answer
The moon does have an atmosphere, but it's extremely thin, and sound does travel in space but you can't hear it.The density is about a billion times less than the Earth's, so in terms of conducting sound waves, it is pretty poor.
Sound is vibrations, doesn't have to be through air. If you had a helmet that conducted vibration, laid down on the surface, and had someone drop a heavy weight, you could hear the impact if the surface was hard enough to transmit it.
Answered by | 04 Mar, 2012, 06:43: PM

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