Question

Calculate the pressure due to a water column of height 100m.(take g =10 ms^2 qnd density of water =1000 kg m ^3)

Answer 1

We have to find the pressure due to a water column of height 100 m.

Given :

• g = acceleration due to gravity = 10 m/s²
• ρ = density of water = 1000 kg/m³
• h = height of water column = 100 m

We know , the pressure due to a water column of height ‘h’ is given by, P = ρgh

= 1000 kg/m³ × 10 m/s² × 100 m

= 10⁶ N/m²

Therefore the pressure due to a water column of height 100 m is 10⁶ N/m².

[ note : Pressure is the force applied in a specific area. so, P = F/A ,

• let the mass of water = m
• and density of water is ρ ,
• if the base area of column is A and height of water is h then Volume of water , V = Ah
• and mass of water , m = ρAh
• force applied = weight of water = mg = ρAhg
• now pressure, P = (ρAhg)/A = ρgh

hence, P = ρgh ,

now you got the formula of pressure at a water column of height h, didn't you? ]