Question

What is the percentage relative humidity on a day, when partial pressure of water vapour is $0.012\times {10}^{5}Pa$ and temperature is ${12}^{\circ }C$.
The vapor pressure of water at this temperature is $0.016\times {10}^{5}Pa$

Answer 1

Percentage Relative humidity ($R.H$) is defined as :
$\text{R.H}=\frac{\text{Partial pressure of water vapour}}{\text{Vapour pressure of water at the same temperature}}\times 100\%$
$\text{R.H}=\frac{0.012\times {10}^{5}Pa}{0.016\times {10}^{5}Pa}\times 100\text{R.H}=0.75\times 100\%=75\%$