Question

An incompressible ideal fluid flows steadily through a pipe that has a change in diameter. The fluid speed at a location where the pipe diameter is 8.0 cm is 1.28 m/s. What is the fluid speed at a location where the diameter has narrowed to 5.0 cm

Answer 1

A V = A X / t where X / t is speed of fluid

A V = area * velocity (rate of fluid flowing)

A1 V1 = A2 V2 form of equation of continuity

pi (D1 / 2)^2 V1 = pi (D2 / 2)^2 V2

V2 = (D1 / D2)^2 * V1 = (8 / 5)^2 * 1.28 m/s = 3.28 km/s