Continuity Equation (A₁v₁ = A₂v₂)

Also known as continuity equation · A₁v₁ = A₂v₂

A1v1=A2v2A_1 v_1 = A_2 v_2

Enter your known values, leave one input blank, and solves for the missing one. Try different units for next level excitement!

Learning zone

Water doesn't pile up inside a pipe, so whatever volume enters one end each second must leave the other — and when the pipe narrows, the fluid has no choice but to speed up in inverse proportion to the area. Squeeze a garden hose to half its area and the jet doubles its speed. The same law shapes rivers (slow and wide, then fast through a gorge) and explains the roar of blood through a narrowed artery that a stethoscope picks up as a bruit.

Continuity Equation (A₁v₁ = A₂v₂)
A1v1=A2v2A_1 v_1 = A_2 v_2
Where
  • A1A_1= Area at point 1
  • v1v_1= Velocity at point 1
  • A2A_2= Area at point 2
  • v2v_2= Velocity at point 2
Missing one of these? Work it out first, then come back