Pressure in Fluids and Atmospheric Pressure — Question 6

As we know,

Pressure due to water column of height h = h ρ g

Given,

density of water = 1000 kg m ^-3

g = 10 m s^-2

P_w on ground floor = 40,000 Pa

P_w on first floor Pwf = 10,000 Pa

In order to know the height of the first floor, let us calculate the difference in pressure

P = P_wg - P_wf = 40,000 – 10,000 = 30,000 Pa

Substituting the values in the formula,

$\text P = \text {h ρ g} \\[0.5em] 30,000 = 1000 \times 10 \times \text h \\[0.5em] \text h = 3\ \text m \\[0.5em]$

Hence, the height of the first floor = 3 m.