phenomena question

Question

How do hot air balloons work?

Can you show a model

Answer 1

Hot air balloons work because as the air inside the balloon is heated, the hot air becomes less dense than the cooler air around it and rises.

Answer 2

Play chess and you'll get it!

Answer 3

As the gas inside the balloon is heated, it expands (increases in volume). The mass of the gas is constant regardless of temperature so the density goes down (Density = Mass/ volume). The balloon will float once the the density of the gas inside of the the balloon is less than the density of the gas outside. (not counting the mass of the balloon basket etc)