Question

sound is a Mechanical wave explain​

Answer 1

Mechanical waves need a medium for propogation.

Sound waves need medium i.e air for propogation. therefore sound waves are called mechanical waves.

Answer 2

the mechanichal waves are those waves which require a medium for propogation. Sound needs a medium (solid, liquid or gas) for their propogation and can't travel without a medium.Therefore sound wave is a mechanical wave.