Materials:
* Two identical balloons
* A string or thread
* A scale (optional, but helpful for a more precise demonstration)
Procedure:
1. Inflate the balloons: Inflate both balloons to the same size.
2. Tie them together: Tie the balloons together with the string so they are hanging at the same height.
3. Observation: Observe the balloons carefully. You will likely notice that they are balanced and hanging at the same level.
4. Deflate one balloon: Carefully deflate one of the balloons completely.
5. Observe the change: You will now see that the balloon that is still inflated has moved upwards, while the deflated balloon hangs lower.
Explanation:
* The inflated balloon contains air, which has weight.
* When you deflate one balloon, you remove the air and its weight.
* The balloon with air still inside is heavier and pulls down more on the string, causing it to rise.
Optional: Using a Scale
If you have a scale, you can quantify this by:
1. Weigh the inflated balloon: Carefully weigh the inflated balloon on the scale.
2. Deflate and weigh again: Deflate the balloon and weigh it again. You will notice a difference in the weight, confirming that the air inside had weight.
Conclusion:
This simple experiment demonstrates that air, even though we can't see it, has weight. The weight of the air inside the balloon pulls down on the string, causing it to rise when the other balloon is deflated.
