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The heart of a resting adult pumps blood at a rate of 5.00 L/min. (a) Convert this to cm 3 /s size 12{"cm" rSup { size 8{3} } "/s"} {} . (b) What is this rate in m 3 /s size 12{m rSup { size 8{3} } "/s"} {} ?

Blood is pumped from the heart at a rate of 5.0 L/min into the aorta (of radius 1.0 cm). Determine the speed of blood through the aorta.

27 cm/s

Blood is flowing through an artery of radius 2 mm at a rate of 40 cm/s. Determine the flow rate and the volume that passes through the artery in a period of 30 s.

The Huka Falls on the Waikato River is one of New Zealand’s most visited natural tourist attractions (see [link] ). On average the river has a flow rate of about 300,000 L/s. At the gorge, the river narrows to 20 m wide and averages 20 m deep. (a) What is the average speed of the river in the gorge? (b) What is the average speed of the water in the river downstream of the falls when it widens to 60 m and its depth increases to an average of 40 m?

Water rushes over a fall.
The Huka Falls in Taupo, New Zealand, demonstrate flow rate. (credit: RaviGogna, Flickr)

(a) 0.75 m/s

(b) 0.13 m/s

A major artery with a cross-sectional area of 1 . 00 cm 2 size 12{1 "." "00"`"cm" rSup { size 8{2} } } {} branches into 18 smaller arteries, each with an average cross-sectional area of 0 . 400 cm 2 size 12{0 "." "400"`"cm" rSup { size 8{2} } } {} . By what factor is the average velocity of the blood reduced when it passes into these branches?

(a) As blood passes through the capillary bed in an organ, the capillaries join to form venules (small veins). If the blood speed increases by a factor of 4.00 and the total cross-sectional area of the venules is 10 . 0 cm 2 size 12{"10" "." 0`"cm" rSup { size 8{2} } } {} , what is the total cross-sectional area of the capillaries feeding these venules? (b) How many capillaries are involved if their average diameter is 10.0 μ m size 12{5 "." "09" times "10" rSup { size 8{7} } } {} ?

(a) 40.0 cm 2 size 12{5 "." "09" times "10" rSup { size 8{7} } } {}

(b) 5 . 09 × 10 7 size 12{5 "." "09" times "10" rSup { size 8{7} } } {}

The human circulation system has approximately 1 × 10 9 size 12{1 times "10" rSup { size 8{9} } } {} capillary vessels. Each vessel has a diameter of about 8 μ m size 12{5 "." "09" times "10" rSup { size 8{7} } } {} . Assuming cardiac output is 5 L/min, determine the average velocity of blood flow through each capillary vessel.

(a) Estimate the time it would take to fill a private swimming pool with a capacity of 80,000 L using a garden hose delivering 60 L/min. (b) How long would it take to fill if you could divert a moderate size river, flowing at 5000 m 3 /s size 12{"5000"`m rSup { size 8{3} } "/s"} {} , into it?

(a) 22 h

(b) 0.016 s

The flow rate of blood through a 2 . 00 × 10 –6 -m size 12{2 "." "00" times "10" rSup { size 8{"-6"} } m} {} -radius capillary is 3 . 80 × 10 9 cm 3 /s size 12{3 "." "80" times "10" rSup { size 8{9} } "cm" rSup { size 8{3} } "/s"} {} . (a) What is the speed of the blood flow? (This small speed allows time for diffusion of materials to and from the blood.) (b) Assuming all the blood in the body passes through capillaries, how many of them must there be to carry a total flow of 90 . 0 cm 3 /s size 12{90 "." 0`"cm" rSup { size 8{3} } "/s"} {} ? (The large number obtained is an overestimate, but it is still reasonable.)

(a) What is the fluid speed in a fire hose with a 9.00-cm diameter carrying 80.0 L of water per second? (b) What is the flow rate in cubic meters per second? (c) Would your answers be different if salt water replaced the fresh water in the fire hose?

(a) 12.6 m/s

(b) 0.0800 m 3 /s size 12{3 "." "80" times "10" rSup { size 8{9} } "cm" rSup { size 8{3} } "/s"} {}

(c) No, independent of density.

The main uptake air duct of a forced air gas heater is 0.300 m in diameter. What is the average speed of air in the duct if it carries a volume equal to that of the house’s interior every 15 min? The inside volume of the house is equivalent to a rectangular solid 13.0 m wide by 20.0 m long by 2.75 m high.

Water is moving at a velocity of 2.00 m/s through a hose with an internal diameter of 1.60 cm. (a) What is the flow rate in liters per second? (b) The fluid velocity in this hose’s nozzle is 15.0 m/s. What is the nozzle’s inside diameter?

(a) 0.402 L/s

(b) 0.584 cm

Prove that the speed of an incompressible fluid through a constriction, such as in a Venturi tube, increases by a factor equal to the square of the factor by which the diameter decreases. (The converse applies for flow out of a constriction into a larger-diameter region.)

Water emerges straight down from a faucet with a 1.80-cm diameter at a speed of 0.500 m/s. (Because of the construction of the faucet, there is no variation in speed across the stream.) (a) What is the flow rate in cm 3 /s size 12{"cm" rSup { size 8{3} } "/s"} {} ? (b) What is the diameter of the stream 0.200 m below the faucet? Neglect any effects due to surface tension.

(a) 127 cm 3 /s

(b) 0.890 cm

Unreasonable Results

A mountain stream is 10.0 m wide and averages 2.00 m in depth. During the spring runoff, the flow in the stream reaches 100,000 m 3 /s size 12{"100,000"`m rSup { size 8{3} } "/s"} {} . (a) What is the average velocity of the stream under these conditions? (b) What is unreasonable about this velocity? (c) What is unreasonable or inconsistent about the premises?

Questions & Answers

how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
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. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
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what's the easiest and fastest way to the synthesize AgNP?
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Cied
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I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
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Yasmin
what is the function of carbon nanotubes?
Cesar
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
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what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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where did you find the research and the first image (ECG and Blood pressure synchronized)? Thank you!!
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Practice Key Terms 2

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Source:  OpenStax, Physics 101. OpenStax CNX. Jan 07, 2013 Download for free at http://legacy.cnx.org/content/col11479/1.1
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