Take a big rubber balloon and inflate it fully. Tie its neck using a thread. Also using adhesive tape, fix a straw on the surface of this balloon. Pass a thread through the straw and hold one end of the thread in your hand or fix it on the wall.
Take a big rubber balloon and inflate it fully. Tie its neck using a thread. Also using adhesive tape, fix a straw on the surface of this balloon.
Pass a thread through the straw and hold one end of the thread in your hand or fix it on the wall.
Ask your friend to hold the other end of the thread or fix it on a wall at some distance. The arrangement is shown in the figure below.
Now remove the thread tied on the neck of balloon. Let the air escape from the mouth of the balloon.
Observe the direction in which the straw moves.
When the air escapes out from the balloon the straw moves in the opposite direction of the air moved out of the balloon.
This activity explains the law of conservation of momentum and Newton’s III law of motion.
Initial momentum = Final momentum
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