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    Question ID:   8625         Current Version: 1
Question: How can balloons fly?
Category: Science > Physics
Keywords: helium, gas, hot air, balloon, fly
Type: how
Rating:(0 ratings)    Views: 216    Discussions: 0   In Watch Lists: 1  

 
    Answer:
There are two ways a balloon can rise: it can (1) be filled with a gas that is lighter than air, such as helium, or (2) it can be inflated with air that is heated sufficiently to make it "lighter" than the air outside of the balloon.

Helium is the second-lightest element, and the main sources for helium are natural gas fields (especially those in the states of Texas, Oklahoma, and Kansas). Heating air makes it less dense, rendering it essentially "lighter." Gas balloons and hot air balloons float because they are lighter than the air they displace.

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