Description
In this exhibit, you can see why a hot air balloon rises. When you press the button, heated air enters the hot air balloon.
When you heat air, it expands. This warm air is lighter than air at normal temperature. Therefore, this air will want to rise above the heavier, colder air and ascend.
If you capture this warm air, for example, as done here in a hot air balloon, the balloon will rise along with the warm air. When the warm air cools down, the hot air balloon will descend again.
This principle is also used in real hot air balloons. Hot air balloons are not only used for pleasure rides but also as weather balloons for atmospheric research. This research is important for predicting the weather.
Birds also use rising warm air, known as thermals. This makes it easier for them to ascend in the air without flapping their wings too much.
Furthermore, the principle of rising warm air and descending cold air is important in designing heating and air conditioning systems.
Why does a hot air balloon rise?
- Press the green button to warm up the hot air balloon.
- Watch on the screen how the temperature inside the balloon goes up.
- Press the red button to release the balloon.
