Answer:
relative humidity
Explanation:
In general, a psychrometer is an instrument composed of two thermometers, used to measure the relative humidity of the air with high precision. As seen in the question above, the two thermometers allow a simultaneous measurement of the temperatures of the wet bulb and the dry bulb. Meteorologists usually use a more efficient form of the psychrometer to measure relative humidity, which is the sling psychrometer.
