Answer the follow

Activity: To show that sound requires a material medium for its propagation

Materials Required: A glass jar fitted with cork and a hole at bottom, electrical connection, electronic bell, vacuum pump

Procedure:

● Make a hole in the cork and make the connections to the electric bell with a switch.

● Make sure the bell is inside the jar and close the jar with the cork.

● At the bottom connect the jar with vacuum pump.

● Now switch on the electric bell. The sound of the bell will come out.

● Now switch on the vacuum pump which will suck the air inside the jar.

● It is observed that the sound of the bell fades gradually and ultimately the sound will not come.