# physics

A 5.4 cm diameter horizontal pipe gradually narrows to 3.7 cm. When water flows through this pipe at a certain rate, the gauge pressure in these two sections is 35.0 kPa and 21.0 kPa, respectively. What is the volume rate of flow?

1. 👍 0
2. 👎 0
3. 👁 163
1. (1/2) rho v^2 + p = constant (Bernoulli)
Q = area* speed = constant

area of big pipe = pi d^2/4 = pi(.054)^2/4 = .00229 m^2

area of small pipe = pi (.037)^2/4 = .00108 m^2

Vsmall = Vbig *.00229/.00108
so
Vsmall = 2.12 Vbig

Pbig = 35*10^3
Psmall = 21*10^3

rho = 1000 kg/m^3

so
35*10^3 + (1/2) (10)^3 Vbig^2 = 21*10^3 + (1/2)(10)^3 (2.12 Vbig)^2

35 - 21 = (1/2)(4.5 - 1) Vbig^2

28 = 3.5 Vbig^2
Vbig = .894 m/s
Q = Area big* Vbig = .00229 m^2 * .894 m/s
= .00205 m/s = 2.05 cm/s

check my arithmetic !

1. 👍 0
2. 👎 0
posted by Damon
2. when i was doing it ... everything was alright until the last part...

(28 = 3.5 Vbig^2
--> Vbig = 2.828 m/s <--
Q = Area big* Vbig = .00229 m^2 * 2.828 m/s
= .00647 m/s = 6.047 cm/s

1. 👍 0
2. 👎 0
3. Stephanie's answer for m/s will also work for m^3/s.

1. 👍 0
2. 👎 0
posted by Wendi

## Similar Questions

1. ### physics

A 6.4 cm diameter horizontal pipe gradually narrows to 5.2 cm . When water flows through this pipe at a certain rate, the gauge pressure in these two sections is 30.0 kPa and 20.2 kPa , respectively

asked by help on April 27, 2017
2. ### physics

A 6.6 diameter horizontal pipe gradually narrows to 3.6 . When water flows through this pipe at a certain rate, the gauge pressure in these two sections is 30.0 and 26.0 , respectively. What is the volume rate of flow? Answer in

asked by anonymous on October 25, 2011
3. ### physics

Water flows through a 4.0-cm-diameter horizontal pipe at a speed of 1.3m/s . The pipe then narrows down to a diameter of 2.0cm . Ignoring viscosity, what is the pressure difference between the wide and narrow sections of the pipe?

asked by Dr.B on March 23, 2018
4. ### Physics

A 7.9cm diameter horizontal pipe gradually narrows to 5.9cm . When water flows through this pipe at a certain rate, the gauge pressure in these two sections is 31.0kPa and 21.0kPa , respectively. What is the volume rate of flow?

asked by Melissa on December 11, 2012
5. ### AP Physics - Fluids

A 6.0-cm diameter horizontal pipe gradually narrows to 4.0 cm. When water flows through this pipe at a certain rate, the gauge pressure in these two sections is 32 kPa and 24 kPa, respectively. What is the volume rate of flow? I

asked by Henry on November 20, 2009
6. ### physic

Water flows through a 4.0-cm-diameler horizontal pipe ata speed uf 1.3 m/s. The pipe then narrows down to a diameter of 2.0 cm. Ignoring viscosity, what is the pressure difference between the wide and narrow sections of the pipe

asked by john on November 19, 2009
7. ### ap physics

A 6.2 cm diameter pipe gradually narrows to 4.0 cm. When water flows through this pipe at a certain rate, the gauge pressure in these two sections is 30.0 kPa and 24.0 kPa, respectively. What is the volume rate of flow?

asked by Anonymous on April 13, 2010
8. ### ap physics

A 6.2 cm diameter pipe gradually narrows to 4.0 cm. When water flows through this pipe at a certain rate, the gauge pressure in these two sections is 30.0 kPa and 24.0 kPa, respectively. What is the volume rate of flow?

asked by Anonymous on April 13, 2010
9. ### Physics

Water flows into one end of a horizontal, cylindrical pipe at 2.0 m/s. The pipe then narrows until its diameter at the opposite end is only 1/3 of that at the beginning. (a) What is the flow speed at the narrow end of the pipe?

asked by Alex on April 15, 2017
10. ### computers

1. Water at a pressure of 3.00 x 10 5th Pa flows through a horizontal pipe at a speed of 1.00 m/s. The pipe narrows to one-fourth its original diameter. What is the speed of the flow in the narrow section?

asked by Anonymous on December 5, 2012

More Similar Questions