Question

Calculate the percentage relative humidity on a day, when partial pressure of water vapour is $8\times {10}^{2}Pa$ and temperature is ${12}^{\circ }C$.
The vapor pressure of water at this temperature is $16\times {10}^{2}Pa$

• A. $50\%$
• B. $200\%$
• C. $100\%$
• D. Cannot be determined.

Answer 1

The correct option is A $50\%$

Percentage Relative humidity ($R.H$) is defined as :
$\text{R.H}=\frac{\text{Partial pressure of water vapour}}{\text{Vapour pressure of water at the same temperature}}\times 100\%$
$\text{R.H}=\frac{8\times {10}^{2}Pa}{16\times {10}^{2}Pa}\times 100\text{R.H}=0.5\times 100\%=50\%$