Sling Psychrometer ( wet and dry bulb temperature):

Sling Psychrometer:

Sling Psychrometer: Both Wet bulb and Dry bulb temperature indicators present in one device and measure the amount of moister air and dry air is called Sling psychrometer.

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This both are arranged in the way that one is above the other, i.e Wet bulb thermometer is arranged below the dry bulb temperature.This used to rotate by the help of hand rotor to increases the velocity of air. Wet bulb thermometer consist of a sock, by this it can dip into the water without wetting the dry bulb thermometer.When the air contains moister percentage is high then the wet bulb thermometer indicates to a high point and when the air is dry it shows low point indication.
by this we can we can calculate the different properties of air like.relative humidity, enthalpy etc.
When there is a mixture of air is present like water vapour and dry air the temperature of Dew bulb, Wet bulb, and Due point temperature indicate equal.

Specific Humidity:

Specific humidity is known when 1 kg of dry air contains the mass of water vapour in it.

Relative Humidity:

This is the ratio of the actual amount of water vapour to the amount of water present in the air at saturated conditions.