Question

Please someone help..A horizontal pipe 10.0cm in diameter has a smooth reduction to a pipe 5.0cm in diameter. If the pressure of the water in the large pipe is 80000Pa and the pressure in the small pipe is 60000Pa at what rate does water flow through the pipe?

Answer 1

rho water = 1000 kg/m^3

P1 + (1/2) rho V1^2 = P1 + (1/2) rho V2^2
and
V1 A1 = V2 A2 so V2 = V1(100/25) = 4 V1

8*10^4 +(1/2)(10^3) V1^2 = 6*10^4 + (1/2)(10^3)(16 V1^2)

solve for V1
then volume flow rate = pi R1^2 V1
or
mass flow rate = 1000 pi R1^2 V1
note R1 = 0.10 meters

Answer 2

Solution