Why does the small density of the gases inside of a hot air balloon make it rise?

Question

I understand how it becomes less dense through the heating process, but why does less density = rising? Does it have to do with the surrounding air being more dense and the two interacting like a bubble in water? Does it have to do with gravity? What's the deal?

Answer 1

Pretty much, yes.
Density = mass per unit volume. [or D=m/v]
So, if something is less dense, it can mean it has less mass. If it has less relative mass, it will rise above things with more relative mass because gravity will cause the more massvie thing to settle below the lighter thing.

Answer 2

Since density of a gas depends on its pressure, molar mass, and temperature, the higher the molar mass and pressure, the more dense the gas. The higher the temperature the less dense the gas. The fact that hotter gas is less dense than a cooler gas explains why hot air rises. The difference between the densities of the hot and cold air is responsible for the lift of hot air baloons.

Answer 3

by cooling, the nice and comfy air molecules require much less area, so the nice and comfy air's density will improve in direction of the exterior air's density. while the balloon can now not grant adequate distinction in air density between interior and outdoors, the balloon starts off to sink.

Answer 4

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Things that are less dense float above things that are more dense. Since the air inside the balloon is less dense than the air outside the balloon, it rises.

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Answer 5

It is actually the difference in the density between the helium and the air outside the balloon that causes the balloon to float.