5th+6th investigated if air has weight. We filled two the of the same balloons with approximately the same amount of air. We stuck each balloon to the either end of a meter stick and hung the meter stick with a string to balance the balloons. The stick remained steady and straight.
We then busrt one of the balloons, letting all the air out. We could see that the weight of the other balloon weighed down the stick therefore proving that air has weight.
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