Water flows at 0.58 m/s through a pipe 11 cm in diameter when the pressure is 450,000 Pa. Determine the water velocity & the pressure in the pipe if it shrinks down to 5 cm in diameter. You can assume that the pipe is horizontal & ρwater = 1000 kg/m3.

Answer 1

Law of mass continuity first:
area*velocity*density=mass flow
PI(11/2)^2*.58m/s*1000kg/m^3= PI*C kg/sec you calculate C.
then on the smaller pipe
C*PI=PI*(5/2)^2*Vs*1000kg/m^3 solve for Vs the outflow.

Now pressure, Write out Bernoullis equation, and solve for P2 on the outlet.