We are studying fluid dynamics in class right now...(adsbygoogle = window.adsbygoogle || []).push({});

Here is a problem that came up on my homework that im not sure how to solve:

When a person inhales, air moves down the bronchus(windpipe) at 10.4 cm/s. The average flow speed of the air doubles through a constriction in the bronchus. Use (density of air) = 1.29 kg/m^3. Assuming an incompressible flow, determine thepressure dropin the constriction. Answer in units of Pa.

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When i first looked at the problem i took"The average flow speed of the air doubles through a constriction"to mean that it goes from 10.4 cm/s to 20.8 cm/s.

Then i just plugged the values into Bernoulli's equation and then plugged the following into my calculator:

x + (1/2)(1.29)(.104) = (x-y) + (1/2)(1.29)(.208).... only solving for y, which would be the pressure drop. i got .020929 Pa as my answer, and this is not correct.

So, unless i made some mistake in the above equations, i assume that"The average flow speed of the air doubles through a constriction"means something else... but im not sure where to start.

Any help is appreciated.

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# Homework Help: Fluid Dynamics/Air flow

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