Question : Cite an experiment to show that sound needs a material medium for its propagation

Question : Cite an experiment to show that sound needs a material medi

1.	Question : Cite an experiment to show that sound needs a material medium for its propagation
Answer» Solution :TAKE an eletric bell and an air tight glass bell jar connected to a vaccum pump. Suspend the bell inside the jar, and PRESS the switch of the bell. You will be able to hear the bell ring. Now pump out the air from the glass jar. The SOUND of the bell will becomes fainterand after some time the sound will not be heard. This is so because ALMOST all air has been pumped out. This shows that sound needs a material medium to travel .