Explain the working of hotair baloon in relation with thermal expansion
Answers
Hot-air balloons float because the air trapped inside the balloon is heated up by a burner, making it less dense than the air outside. Here's another way to think of it. You've probably heard people say that heat rises, by which they really mean that hot air rises.
Hot air rises and the heated air molecules spread out or expand and bounce around, and the space becomes less dense than the surrounding space. On increasing the temperature of the air inside the balloon envelope by the burner, it becomes less dense than the air, thus making it lighter than air. Hence the hot air ballon rises up. The difference between the temperature inside and outside of the envelope, and the weight that is being lifted decides the amount of lift of the hot air ballon.