An Explanation of Hot Air Balloons
Ever wanted to finally grasp the concepts of how hot air balloons do the “balloon thing”? All throughout growing up, it was probably always super easy to pin them to “magic” or something else that could explain the world as a place where things just happen to make life better; but as you get older, things start to become a lot more logical and you find out that almost every phenomenon can be scientifically explainable. In this post, we’ll be explaining the subject of how hot air balloons “do their balloon thing” in order to put your curious child brain at ease.
To understand how hot air balloons works, we have to have a somewhat basic understanding of the main gas laws. The main gas laws and their definitions are listed below:
Amonton's Law - The Relationship Between Pressure & Temperature
Formula: P1/P2 = T1/T2
Avogadro’s Law - The Relationship Between Moles of a Material & Volume
Formula: V1/n1 = V2/n2
Boyle’s Law - The Inverse Relationship Between Pressure & Volume
Formula: P1 V1 = P2 V2
Charles’ Law - The Relationship Between Temperature & Volume
Formula: V1 / T1 = V2 / T2
Gay-Lussac’s Law - The Relationship Between Pressure & Temperature
Formula: P1 / T1 = P2 / T2
If these definitions aren’t cutting it for you, feel free to check out this source for a more scientific perspective!
Hot air balloons are able to work because it is not a closed system. When the balloon is heated it already is filled with air, but the heat makes the particles speed up and take up more space; because the balloon has vents some the particles escape making the inside of the balloon less dense than the air outside of it if you notice this is Charles’ Law. When the balloon needs to reduce altitude the heat is turned of and as the particles inside the balloon cool and start to slow down they take up less space, so other particles enter the balloon.
Now that you know basic gas laws you know how hot air balloons work, now you have a different perspective on how hot air balloons work. You will always look at a hot air balloon and remember how the gas laws work to make the balloon go up and down. Just remember that you can use the Ideal Gas law (PV=nRT) and you can manipulate the equation to get any of the other gas laws.