Question

Sound cannot travel in vacuum. Describe an experiment to demonstrate this.

Answer 1

Well since sound is a mechanical wave it cannot travel through vacuum

A simple experiment which I remember studying at high school is the Bell-Jar experiment

(A bell jar is a lab equipment which is used for creating a vacuum)

Place an electric bell inside of a bell jar and then pump out the air present in the sealed bell jar as pumping out the air you can understand that the sound coming from the bell jar fades to a point which we are unable to hear anything coming from the jar (vacuum state).

Thus proves that sound needs a medium in order to travel.

Answer 2

sound need any medium to travel. in vacuum there is no medium for travelling of sound. Hence sound don't travel in vacuum.