Aim: (a) To prove that air has mass/weight. Procedure: Take a stick or a staw. Tie a thread at its centre and hang it so that it so that it remains horizontal. Tie two opposite ends of the stick as shown in the diagram. keep the stick in prefect horizontal position. Now remove one balloon and inflate it with air. Again tie it at the original end.

Observation: Tick ✓ the appropriate answers:
1) Does the stick remain in the horizontal position now?( Yes/No)
2) What happens to the stick at the side of the inflated balloon?( It goes up/ It goes down)

Influence:​