What instrument is commonly used to measure humidity?

The instrument that is most commonly used to measure humidity is a hygrometer. Hygrometers are specifically designed to measure the amount of moisture present in the air. There are various types of hygrometers, including digital hygrometers, which provide readings through electronic sensors, and analog hygrometers, which use materials that change with humidity levels, such as human hair or certain chemicals.

Understanding humidity is crucial because it affects weather patterns, human comfort, and many ecological processes. By measuring humidity accurately, hygrometers help in forecasting weather and studying climate conditions.

In contrast, thermometers are used to measure temperature, barometers measure atmospheric pressure, and anemometers measure wind speed. These instruments serve different purposes and do not provide information about moisture content in the air like hygrometers do.