FAA Ground School Practice Test

Which of the following conditions can lead to condensation?

1. High temperatures and low humidity

2. Cooling of air to its dewpoint

3. Heating of air to above its saturation point

4. Rapid changes in atmospheric pressure

The correct answer is: Cooling of air to its dewpoint

The correct answer, cooling of air to its dewpoint, is essential for understanding how condensation occurs. When air is cooled to its dewpoint temperature, it reaches a critical point where it can no longer hold all the moisture in vapor form. As the air cools, the water vapor molecules slow down and begin to congregate, forming tiny water droplets, which we perceive as condensation. This process is fundamental to the formation of clouds, fog, and dew. High temperatures and low humidity do not typically lead to condensation because warm air can hold more moisture, and the low humidity indicates that the air is already dry. Heating air above its saturation point usually causes it to remain in vapor form since warmer air can hold even more moisture before condensation occurs. Rapid changes in atmospheric pressure might influence weather patterns, but they do not directly lead to condensation the way cooling air to the dewpoint does. Understanding these concepts is crucial for recognizing weather phenomena and the behavior of moisture in the atmosphere.