/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 54 A viscous liquid is flowing stea... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

A viscous liquid is flowing steadily through a pipe of diameter \(D .\) Suppose you replace it by two parallel pipes, each of diameter \(D / 2,\) but the same length as the original pipe. If the pressure difference between the ends of these two pipes is the same as for the original pipe, what is the total rate of flow in the two pipes compared to the original flow rate?

Short Answer

Expert verified
Based on the given information and using the Hagen-Poiseuille equation, we have calculated the flow rates for the original pipe and the two parallel pipes. Through our analysis, we found that the total flow rate in the two parallel pipes is twice the original flow rate. Therefore, the flow rate in the two parallel pipes is 2 times the flow rate in the original pipe.

Step by step solution

01

Calculate the flow rate for the original pipe

First, we need to calculate the flow rate for the original pipe with diameter D and length L. Using the Hagen-Poiseuille equation: $$Q_{original} = \frac{\pi {(D/2)^4} \Delta P}{8 \eta L}$$
02

Calculate the flow rate for each of the new pipes

Next, we need to calculate the flow rate for each of the parallel pipes with diameter D/2 and length L. Using the Hagen-Poiseuille equation for the new pipes: $$Q_{new} = \frac{\pi {((D/2)/2)^4} \Delta P}{8 \eta L}$$ $$Q_{new} = \frac{\pi {(D/4)^4} \Delta P}{8 \eta L}$$
03

Calculate the total flow rate for the two parallel pipes

Now, we have two parallel pipes, so the total flow rate is the sum of the flow rates for each of the new pipes: $$Q_{total} = 2 \times Q_{new} = 2 \times \frac{\pi {(D/4)^4} \Delta P}{8 \eta L}$$
04

Compare the total flow rate with the original flow rate

Finally, we can calculate the ratio of the total flow rate of the parallel pipes to the original pipe flow rate: $$Ratio = \frac{Q_{total}}{Q_{original}}$$ Substitute the values of \(Q_{total}\) and \(Q_{original}\): $$Ratio = \frac{2 \times \frac{\pi {(D/4)^4} \Delta P}{8 \eta L}}{\frac{\pi {(D/2)^4} \Delta P}{8 \eta L}}$$ Simplify the expression: $$Ratio = \frac{2 \times (D / 4)^4}{(D / 2)^4} = \frac{2 \times (D^4/2^8)}{(D^4/2^8)} = 2$$ So, the total flow rate in the two parallel pipes is 2 times the original flow rate.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

The pressure in a water pipe in the basement of an apartment house is $4.10 \times 10^{5} \mathrm{Pa},\( but on the seventh floor it is only \)1.85 \times 10^{5} \mathrm{Pa} .$ What is the height between the basement and the seventh floor? Assume the water is not flowing; no faucets are opened.
A dinoflagellate takes 5.0 s to travel 1.0 mm. Approximate a dinoflagellate as a sphere of radius \(35.0 \mu \mathrm{m}\) (ignoring the flagellum). (a) What is the drag force on the dinoflagellate in seawater of viscosity $0.0010 \mathrm{Pa} \cdot \mathrm{s} ?$ (b) What is the power output of the flagellate?

The average density of a fish can be found by first weighing it in air and then finding the scale reading for the fish completely immersed in water and suspended from a scale. If a fish has weight \(200.0 \mathrm{N}\) in air and scale reading \(15.0 \mathrm{N}\) in water, what is the average density of the fish?

A plastic beach ball has radius \(20.0 \mathrm{cm}\) and mass \(0.10 \mathrm{kg},\) not including the air inside. (a) What is the weight of the beach ball including the air inside? Assume the air density is \(1.3 \mathrm{kg} / \mathrm{m}^{3}\) both inside and outside. (b) What is the buoyant force on the beach ball in air? The thickness of the plastic is about 2 mm-negligible compared to the radius of the ball. (c) The ball is thrown straight up in the air. At the top of its trajectory, what is its acceleration? [Hint: When \(v=0,\) there is no drag force.]

Near sea level, how high a hill must you ascend for the reading of a barometer you are carrying to drop by 1.0 cm Hg? Assume the temperature remains at \(20^{\circ} \mathrm{C}\) as you climb. The reading of a barometer on an average day at sea level is $76.0 \mathrm{cm}$ Hg. (W) tutorial: gauge)
See all solutions

Recommended explanations on Physics Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.