Question

why sound waves are known as mechanical waves?

Answer 1

Sound waves need a medium, solid or liquid or gas for their propagation and cannot travel without a medium.
The velocity of sound in a medium depends on its mechanical properties. 

Therefore, sound waves are known as mechanical waves.

Hope it helps :-)

Answer 2

Hi there !!!

=> Sound is a form of Energy

=> It is very clear to us from the Bell Jar experiment that sound needs a medium for its propagation

=>The medium for its propagation can be solid , gas or liquid.

=>Hence , without a medium , sound cannot travel.

=> Mechanical waves also require a material medium for its propagation.

=> Hence , sound wave are called mechanical waves.

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