ANS:A - dew point

A psychrometer does not measure the dew point temperature of moist air. Explanation:

• A psychrometer, also known as a wet and dry bulb thermometer, consists of two thermometers: a dry bulb thermometer and a wet bulb thermometer.
• The dry bulb thermometer measures the dry bulb temperature, which is the ambient air temperature.
• The wet bulb thermometer measures the wet bulb temperature, which is the temperature of air when water evaporates from a wet surface, causing cooling due to evaporative cooling.
• By comparing the readings of the dry bulb and wet bulb thermometers, various properties of the air, such as relative humidity and humidity ratio, can be determined.
• The dew point temperature is the temperature at which air becomes saturated with water vapor, leading to the condensation of moisture. It is not directly measured by a psychrometer.
• However, the dew point temperature can be indirectly calculated using the dry bulb and wet bulb temperature readings obtained from a psychrometer, along with appropriate psychrometric charts or equations.