What does a sling psychrometer measure?

A sling psychrometer is an instrument specifically designed to measure both wet and dry bulb temperatures, which are essential for calculating various atmospheric conditions related to humidity. The device consists of two thermometers, where one has a dry bulb surrounded by a sensor and the other has a bulb moistened with water (the wet bulb).

As air moves over the wet bulb, evaporation occurs, causing the temperature reading of the wet bulb to drop compared to the dry bulb. By comparing these two temperatures, you can derive relative humidity, dew point temperature, and the number of grains of moisture in the air.

This dual measurement is fundamental because it provides a direct method to assess the moisture content in the air and to understand its thermal properties, which are critical in applications such as HVAC systems and weather forecasting. Therefore, recognizing that a sling psychrometer measures both wet and dry bulb temperatures is crucial for understanding how this tool functions in the context of humidity measurement.