Which instrument measures dew point by comparing dry-bulb and wet-bulb temperatures?

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Multiple Choice

Which instrument measures dew point by comparing dry-bulb and wet-bulb temperatures?

Dew point is found from humidity information gathered by comparing two thermometer readings. A psychrometer has a dry-bulb thermometer that reads the ambient air temperature and a wet-bulb thermometer whose bulb is wrapped in a wick soaked with water. As air moves past, evaporation cools the wet bulb, so the wet-bulb temperature drops more in dry air and less in humid air. The difference between the dry-bulb and wet-bulb readings tells you the humidity, and from that humidity you can determine the dew point—the temperature at which air would become saturated if cooled further. This makes the psychrometer the instrument used to measure dew point via the dry-bulb and wet-bulb comparison. Other instruments don’t measure humidity or dew point: a barometer measures atmospheric pressure, a thermometer measures temperature, and an anemometer measures wind speed.

Dew point is found from humidity information gathered by comparing two thermometer readings. A psychrometer has a dry-bulb thermometer that reads the ambient air temperature and a wet-bulb thermometer whose bulb is wrapped in a wick soaked with water. As air moves past, evaporation cools the wet bulb, so the wet-bulb temperature drops more in dry air and less in humid air. The difference between the dry-bulb and wet-bulb readings tells you the humidity, and from that humidity you can determine the dew point—the temperature at which air would become saturated if cooled further. This makes the psychrometer the instrument used to measure dew point via the dry-bulb and wet-bulb comparison. Other instruments don’t measure humidity or dew point: a barometer measures atmospheric pressure, a thermometer measures temperature, and an anemometer measures wind speed.

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