All students should develop abilities necessary to do and understand scientific inquiry. All students should develop abilities of technological design and an understanding about science and technology. All students should develop abilities necessary to do and understand scientific inquiry. All students should develop abilities of technological design and an understanding about science and technology. A hygrometer measures either the relative or absolute amount of water vapor in the air.
Nature responds to both quantities of humidity.
The relative amount of moisture in the air determines how much evaporation takes place from a liquid water source, such as from a pond, leaf, soil surface, or raindrop. The absolute amount of moisture in the air determines how much energy in the form of latent heat is stored in the air. When water vapor condenses, energy in the form of heat is given to the remaining air molecules. If large amounts of water vapor can condense, the greater the heating of the local air molecules. Two different hygrometers can be built in this activity.