How does wet and dry bulbs thermometer work?

A wet and dry bulb thermometer consists of two thermometers: one with a dry bulb that measures air temperature and another with a wet bulb, which has a moist cloth covering its bulb. As water evaporates from the wet bulb, it cools down, and the temperature difference between the two thermometers indicates humidity levels. The greater the difference, the lower the humidity; conversely, a smaller difference indicates higher humidity. This principle is used in various applications, including meteorology and HVAC systems, to assess moisture in the air.