Hot Air Balloon: The Science Behind Floating

How does a hot air balloon float?

The weight of the air displaced is less than the volume of the balloon

A hot air balloon floats due to the principle of buoyancy and the difference in density between the hot air inside the balloon and the cooler air outside. The balloon is able to float because the weight of the air displaced by the balloon is less than the weight of the volume of the air inside the balloon. This creates an upward force, allowing the balloon to rise and float in the air.

Hot air balloons work by heating the air inside the balloon using a burner that heats liquid propane to create a large flame. This heat increases the temperature and therefore decreases the density of the air inside the balloon. As a result, the hot air becomes lighter than the surrounding cooler air, creating buoyant force that lifts the balloon.

Archimedes' Principle explains this phenomenon, stating that a body immersed in a fluid experiences an upward force equal to the weight of the fluid it displaces. In the case of a hot air balloon, the warm air inside weighs less than the outside air, leading to the balloon floating upwards.

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