# GATE2017 ME-2: 15

If a mass of moist air contained in a closed metallic vessel is heated, then its

1. Relative humidity decreases.
2. Relative humidity increases.
3. Specific humidity increases.
4. Specific humidity decreases.

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Ans: A

This case can be considered as  a case of sensible heating, hence the relative humidity decreases keeping the specific humidity constant and an increase in DBT (dry bulb temperature)
540 points 1 2 8

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