Liquid Pressure
In this post, we will discuss Liquid Pressure and related topics.
What is liquid pressure | What is liquid pressure for class 8
Liquid pressure is the pressure exerted by Liquids on their container and on any object in the liquid inside the container.
Properties of liquid pressure | Laws of liquid pressure
Liquid pressure:
- acts in all directions
- increases with depth
- increases with the density of the liquid
Liquid pressure formula derivation
Let’s derive a formula for the pressure P at a depth h in a liquid of density ρ.
Consider a frame with an area A in the liquid (figure 1). The liquid within this frame is in equilibrium with the liquid outside it. The liquid inside the frame has a volume of A × h and a mass of ρ × A × h.
The weight of the liquid is therefore g ×ρAh (where g is the acceleration due to gravity).
The weight of this liquid acts downwards on the liquid below it; this is the force in the equation that defines pressure.
The pressure p at the depth h in the liquid is, therefore, P = ρAgh/A = ρgh
Liquid pressure formula
Pressure P at a depth of h in a liquid of density ρ is expressed with the following formula:
P = ρgh
