Pressure is defined as force per unit area of the surface. The SI unit of pressure, pascal is shown below :
1 Pa = 1 N\text{m}^{-2}
If mass of air at sea level is 1034 g \text{cm}^{-2}, calculate the pressure in pascal.
Pressure is force (i.e., weight) acting per unit area
But weight = mg
∴ Pressure = Weight per unit area
= \frac{1034 \text{g}}{\text{cm}^2} \times 9.8 \text{ ms}^{-2}
= \frac{1034\ \text{g}}{\text{cm}^2} \times 9.8 \text{ ms}^{-2} \times \frac{1\ \text{kg}}{1000\ \text{g}}
\times\ \frac{100\ \text{cm}\ \times\ 100\ \text{cm}}{1\ \text{m}\ \times\ 1\ \text{m}} \times \frac{1\ \text{N}}{\text{kg m s}^{-2}} \times \frac{1\ \text{Pa}}{1\ \text{Nm}^{-2}}
= 1.01332 × \pmb{10^5} Pa