How do you use a wet bulb thermometer and a dry bulb thermometer?

Answer 1

as the air passes over the wet bulb thermometer the water in the cloth evaporates. as the water evaporates the cloth cools. if the humidity is low the water will evaporate more quickly and the temperature reading on the wet bulb thermometer will drop. if the humidity is high only a little bit of water will evaporate from the cloth of the wet bulb thermometer and the change in temperature will be small.

Answer 2

The wet and dry bulb thermometers are used in conjunction with each other to determine relative humidity.

The Dry Bulb temperature (by itself) measures ambient air temperature. The "Dry Bulb" identification indicates that this temperture is not affected by humidity. The Dry Bulb Temperature refers basically to the ambient air temperature. It is called "Dry Bulb" because the air temperature indicated by a thermometer not affected by the moisture content (humidity) of the air.

The Wet Bulb temperature is trchnically called "the temperature of adiabatic saturation" It is measured by a thermometer with its bulb wrapped in moist cloth or cotton fiber. Aair passing over the wet bulb evaporates the water from the cloth and cools the bulb.

The temperature difference between the dry bulb and wet bulb depends on the humidity of the air. The two tempertures can be placed on a Psychometric diagram (also called a Mollier chart) to determine relative humidity at the dry bulb temperature.