Final answer:
Warmer air has a greater capacity to hold more moisture because hot air can contain a higher volume of water vapor before reaching saturation. Relative humidity measures the water vapor content in the air compared to its maximum at a given temperature, and it is lowest in warm air.
Step-by-step explanation:
The type of air that has a greater capacity to hold more moisture is warmer air. Relative humidity is the term used to describe how much water vapor is present in air compared to the maximum amount it can hold at a certain temperature. When the air is warmer, the relative humidity decreases because warm air can contain a higher volume of water vapor before it reaches saturation. As the temperature drops, relative humidity increases, and may reach 100% at the dew point, which is the temperature at which the air is fully saturated with water vapor and can lead to the formation of fog or dew if conditions are right.
Therefore, if one wants to dry something effectively, it is advantageous to use hot air versus cold air. The increased temperature boosts the energy of the water molecules, enhancing the evaporation rate. This illustrates why hot air has a higher capability to hold moisture, leading to a more efficient drying process.