Published: August 26, 2019
Total Running Time: 00:01:17
Clouds form when invisible water vapor in the air cools enough to form tiny droplets of liquid water. In the atmosphere, this usually happens when moist air rises to higher altitudes. At higher altitudes, the pressure is lower, so the gas expands, loses internal energy, and cools. You can create the same effect by rapidly expanding the air in a jar.