Question

The relative humidity on a day, when partial pressure of water vapour is $0.012 \times 10^{5}Pa$ at 12°C is (take vapour pressure of water at this temperature as $0.016 \times 10^{5}Pa$)

• A. 70%
• B. 40%
• C. 75%
• D. 25%

Answer 1

Answer: (C)

75%

Answer 2

Partial pressure of water vapour

$P_{W} = 0.012 \times 10^{5}Pa$,

Vapour pressure of water $P_{V} = 0.016 \times 10^{5}Pa$.

The relative humidity at a given temperature is given by $= \frac{\text{Partial pressure of water vapour}}{\text{Vapour pressure of water}}$

$= \frac{0.012 \times 10^{5}}{0.016 \times 10^{5}} = 0.75 = 75\%$