please help?

Question

A viscous oil flows through a narrow pipe. If the diameter of the pipe were doubled, the flow rate should increase by how many? 2,4,6,8,16. Please explain or show equation.

Answer 1

Roughly by 4, since the cross sectional area of the pipe is multiplied by 4 (A=πr²) and so the resistance to flow (restriction) is roughly one fourth (assuming that the pressure stays constant).


Doug