Eli5: How can hot air balloons fly by only using fire?
In: Other
Temperature is inversely proportional to density as temperature increases, vibration in molecules(for solids and for gases I think it’s kinetic energy(0.5kt^2) and they move faster)increases and space between them increases, decreasing the density. Hot air balloon uses fire to increase the temperature of the air, decreasing it’s density relative to the air around it, there by creating buoyancy (lift or upward force). Air is a fluid just like liquid. Since buoyant force is more than weight (earth pulling stuff towards itself), net force is in the upward direction and the hot air balloon moves up. Same can be assumed for airships filled with hydrogen/helium
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