Answer:
A sling psychrometer is a device used to measure relative humidity, which is the amount of moisture in the air compared to the maximum amount the air can hold at a given temperature. The sling psychrometer consists of two thermometers, one of which has a wet bulb covered with a wick dipped in water, and the other has a dry bulb that is exposed to the air.
To use a sling psychrometer in two different locations and determine which location has lower relative humidity, follow these steps:
Wet the wick of the wet bulb thermometer with distilled water.
Swing the psychrometer around in the air for a minute or two to allow the water to evaporate from the wet bulb.
Record the temperature reading on both the wet bulb and dry bulb thermometers at each location.
Calculate the difference between the wet bulb and dry bulb temperatures, known as the wet bulb depression, for each location.
Use a psychrometric chart or calculator to determine the relative humidity for each location based on the dry bulb temperature and wet bulb depression.
Compare the relative humidity readings for each location. The location with the lower relative humidity reading has drier air and therefore lower moisture content.
Note that the sling psychrometer must be used correctly and calibrated properly to obtain accurate readings. Also, the relative humidity can vary within a given location depending on factors such as time of day, weather conditions, and proximity to bodies of water. Therefore, it is best to take measurements at multiple times and locations to obtain a more accurate picture of the relative humidity in each area.