Question

Put a stainless steel glass on your mouth and suck air from it. It will stick to your mouth. Why?​

Answer 1

Answer:

Take a metal or glass tumbler. Make sure that it is dry. Place a cell phone in it. Ask your

friend to give a ring on this cell phone from another cell phone. Listen to the ring

carefully. Now, surround the rim of the tumbler with your hands. Put your mouth on the

opening between your hands. Indicate to your friend to give a ring again. Listen to the

ring while sucking air from the tumbler.

Answer the following questions:

(i) Does the sound become fainter as you suck air?

(ii) Remove the tumbler from your mouth. Does the sound become loud again?

(iii) Is it possible that the decreasing amount of air in the tumbler had something to do

with decreasing loudness of the ring?

(iv) What do you conclude from this activity?