How do helium balloons work?

By Curt S.


How do Helium balloons work/Helium Air ship
A helium balloon floats because of its density. Helium has less density then air so it makes things float. If something is has less density then air it will float, if it has more it will not float. Helium air ships work because there are compartments inside the envelope that have air in them and there called ballonets. The ballonets pump air out of or into them self’s which decrease or increases the amount of density, which makes it ascend or descend. Helium reduces weight
air ballon.jpg
Figure 1 Airship

of the air ship so it will float. If you would like to learn about other flying machines you can look at gliders.

Helium and Density
Helium makes materials float like balloons and toys. Helium is a substance that has no color, no taste or no smell. It is also a gas that will not burn or will not interact with other elements. Helium is found in the atmosphere of stars, helium is created in a star. It is created by in a star by atoms of other elements and hydrogen combine. Helium floats because it is so light and it has a density less then air. Air has the density of 1.29km and helium has the density of 0.1785 which is less than air so it floats. Every substance has its own density. Density applies to substances in the air and in the water. If something has less density than water it floats and if it has more density than water it sinks.



density.jpg
Figure 2 Density

What’s the difference between hydrogen, helium and hot air and what are some similarities?
All three of these gases make balloons float in the air. Hydrogen is flammable substance and it is not safe to use in balloons so many people don’t use it. Most people use hot air or helium.
he;ium.jpg
Figure 3 helium molecule
Helium is the most used but the only bad part is that it is very expensive. Helium is less buoyant so it is the mot ideal for balloons unlike

hot air and hydrogen. Helium is mostly used for large balloons but also for party balloons at children birth day parties. Out of all three gases hydrogen is the lightest.


Glossary
Ballonets- ballonets are things in air ships that push air in or out so the balloon will increase in the air or decrease in the air
Density- Density is the matter of something that lets it float or sink.
Decreasing – is were something does down like an air plane decreasing altitude
Increases- is were something goes up like an air ship

Citations
Brain, Marshall. "How Helium Balloons Work" 01 April 2000. HowStuffWorks.com. <http://science.howstuffworks.com/helium.htm> 26 September 2012.

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Encyclopædia Britannica, Inc., 2012. Web. 14 Sept. 2012.

<http://school.eb.com/all/comptons/article-9599545

helium. (2012). In Britannica Elementary Encyclopedia. Retrieved from http://school.eb.com/all/elementary/article?articleId=353238 Encyclopædia Britannica Online School Edition, s.v. "helium," accessed September 14, 2012, http://school.eb.com/all/elementary/article?articleId=353238. helium 2012. Encyclopædia Britannica Online School Edition. Retrieved 14 September 2012

Judson, Knight. Science of everyday things. Detroit: Gale group,2002. Print.

Neil, Ardley.how things work . NY: Pleasantville,1995. Print.