Summary
1 A 1 v1 =
2 A 2 v2
For many situations -- for most situations involving a liquid but not a gas -- we can assume the density does not change. This is called an incompressible fluid. For those cases,
A 1 v1 = A 2 v2
(1/2)v2 + P +
g y = constant
or
(1/2) 1 v12 + P1 +
1 g y1 = (1/2)
2 v22 + P2 +
2 g y2
If the vertical height y does not change, this means
(1/2) v2 + P = constant
or
(1/2) 1 v12 + P1 = (1/2)
2 v22 + P2
(c) 2002, Doug Davis; all rights reserved
Applications Homework Return to ToC, Fluids in Motion