Pressure Distribution in a Static Fluid

Question 1

Pressure variation in a static fluid

Answer 1

*A fluid at rest has constant pressure across a horizontal plane
* That’s why liquid surfaces are flat and horizontal
*but there IS a pressure gradient in the vertical direction

Question 2

How does pressure vary with depth?

Answer 2

▪ Consider a small element of stationary
fluid
▪ As the fluid is at rest, no shear forces
apply and pressure is constant along any
horizontal plane
▪ Equilibrium:
E Forces = 0

Question 3

how pressure varies in a static liquid is:

Answer 3

Pressure at bottom = pressure at top + pgh

Question 4

Absolute & gauge pressure

Answer 4

▪ Absolute pressure is measured relative to zero pressure (vacuum)
▪ Gauge pressure = absolute pressure - atmospheric pressure