Artery has a gauge pressure of 10^4 Pa. Why would this be more than atmospheric pressure, which I thought was 10^5 Pa? TBR GChem 2, fluids, passage 3 on pg 96.
Pressure question; pascals.
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awwww sheeeiiittt.
I remember this question and was freaking out about it too.
The passage actually says "gauge pressure" for the arterial pressure.
That actually means relative to atmospheric pressure (so 10^4 on top of atm).
I remember this question and was freaking out about it too.
The passage actually says "gauge pressure" for the arterial pressure.
That actually means relative to atmospheric pressure (so 10^4 on top of atm).
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TBR has several associated passage problems where the answer is "artery pressure is higher."
But it's difficult to figure out if you don't know that
Total P= Atm+Gauge
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Except in the pleural space by the lungs?
Yeah what some other people said. It was like, "the gauge pressure is 10^4". I'm like, okay, so it's less than ATM pressure, which is 10^5.
Yeah, I figured it out--WHEN I GOT THE QUESTION WRONG.
I mean if it says gauge, how are we supposed to assume it means Patm+pgH?
Yeah, I figured it out--WHEN I GOT THE QUESTION WRONG.
I mean if it says gauge, how are we supposed to assume it means Patm+pgH?
its not negative its lower than atmospheric
dP = rho*g*dh
it can get confusing when you have to subtract or add the gauge pressure but i think the MCAT would be clear on that
it can get confusing when you have to subtract or add the gauge pressure but i think the MCAT would be clear on that
Okay, I just wanted to make sure I wasn't ****ing up the definition. Pgauge is NOT Ptotal, which is Psurface+Patm. Pgauge is proportional to depth, whereas Ptotal is Psurface at the y intercept. I was so thoroughly confused when I got that wrong. "But...10^5 Pa is atmospheric, and this is 10^4 and 10^3....what?!)
Okay, I just wanted to make sure I wasn't ****ing up the definition. Pgauge is NOT Ptotal, which is Psurface+Patm. Pgauge is proportional to depth, whereas Ptotal is Psurface at the y intercept. I was so thoroughly confused when I got that wrong. "But...10^5 Pa is atmospheric, and this is 10^4 and 10^3....what?!)
Pgauge is literally = rho*g*h think of it as the OVER pressure or UNDER pressure
Ptotal = Patm + pgh or Ptotal = Patm + (+/-Pgauge)
Pgauge = rho*g*dh
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