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Name: Gina
Status: Student
Age: 16
Location: N/A
Country: N/A
Date: N/A 

Why is a weather balloon never filled completely with He when it is released?

As the balloon rises, the atmospheric pressure decreases. The volume of the gas of the balloon will then increase. Therefore, the balloon needs expansion room for the gas.

Nathan A. Unterman


At ground level, atmospheric pressure is much higher than up high. If the balloon were completely filled, as the pressure outside the balloon dropped as it flew higher, the balloon would try to expand to equalize the pressure, and it would pop.

Donald Yee Ph.D.

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