Ncert Exercises & Solutions

1.13 Pressure is determined as force per unit area of the surface. The SI unit of pressure, pascal is as shown below:

1Pa = 1N m^–2

If the mass of air at sea level is 1034 g cm–2, calculate the pressure in pascal.

Pressure is defined as force acting per unit area of the surface.

$P = F / A = 1034 g / c m^{2} \times 9.8 m / s^{2} = 1034 / 1000 \times 100 \times 100 k g / m^{2} = 1.01332 x 105 k g m - 1 s - 2$

We know,
1 N = 1 kg m/ $s^{2}$
Then,
$1 P a = 1 N / m^{2} = 1 k g m - 2 s - 2 P a = 1 k g m - 1 s - 1 P r e s s u r e = 1.01332 \times 10^{5} P a$