MCAT "rules"

[MedPR]

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So in EK physics it says "all liquids are ideal, unless otherwise indicated." I don't think the MCAT will make it a point to tell us that blood is not an ideal fluid. So should we answer questions about blood based on the real flow or based on what is predicted by ideal flow?

In other words, Bernoulli's equation says that pressure and cross-sectional are are inversely related. But blood in the aorta has the highest pressure even though the Aorta is the largest vessel in the body.

Probably a dumb question, but I don't want to start this EK 30 minute just yet so I'm delaying any way possible 🙂

 

[milski]

So in EK physics it says "all liquids are ideal, unless otherwise indicated." I don't think the MCAT will make it a point to tell us that blood is not an ideal fluid. So should we answer questions about blood based on the real flow or based on what is predicted by ideal flow?

In other words, Bernoulli's equation says that pressure and cross-sectional are are inversely related. But blood in the aorta has the highest pressure even though the Aorta is the largest vessel in the body.

Probably a dumb question, but I don't want to start this EK 30 minute just yet so I'm delaying any way possible 🙂

Keep it ideal unless you have a strong indication that it's the opposite. Usually the non-ideal cases are much more more complicated.

The aorta example is not related to ideal/non-ideal. Bernoulli's equation applies only if you have the same flow. Since the aorta will split into arteries and they'll split further, you cannot apply Bernoulli directly to that.

The aorta having the highest pressure is a very good thing, if you want to move the fluid from the aorta towards other "tubes" where the pressure is lower.

 

[davcro]

Assume ideal. The most probable non-ideal situation I can think of is turbulent flow, which occurs when you measure blood pressure with a cuff.

Fluids gets insanely complicated in non-ideal situations.