"An artery of radius 1 mm leaves the heart and travels upward 0.3 m to your shoulder, where it breaks into 3 smaller veins, each of radius 0.5 mm. Blood flows through the artery at a speed of 0.8 m/s as it leaves the heart. The density of blood is 1050 kg/m^3."(adsbygoogle = window.adsbygoogle || []).push({});

I determined that the blood moves at 1.07 m/s in the smaller veins, which is correct.

I am suppose to find the difference in pressure "between a point in the artery just as it leaves the heart and a point in one of the smaller veins just at the point where they split off"

I am pretty sure I am suppose to use bernoulli's Eqn.

P1 + d*g*y1 + 1/2 *d*v1^2 = P2 + d*g*y2 + 1/2 *d*v2^2

P1 + (1050 kg/m^3)(9.8 m/s^2)(0.3m) + (1/2)(1050kg/m^3)(0.8m/s)^2 = P2 + 0 + (1/2)(1050kg/m^3)(1.07m/s)^2

I have everything to use this equation, but the initial pressure. Am I missing a way to figure that out? I can't seem to get any of my pressure equations to work for this, P = F/A, P = P0 + dgh

The answer is suppose to be 3341 pascals

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# Homework Help: Pressure and Bernoulli's Eqn

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