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pianoman2700
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[SOLVED] Fluids and Forces
Hi, I'm new to this site, so I'm not sure if this is the right place to post. I found a year-old entry with the same question that I'm having trouble with, found here:
https://www.physicsforums.com/showthread.php?t=153538"
For Part a, I followed the same method that PremedBeauty followed, but can't seen to get the correct answer. Is there a force that I am missing?
For Part b, I integrated to try and find the total force, but, once again, my answer comes out incorrect. My calculations for part b are below.
F=force
(atm)= atmospheric pressure (in Pascals)
p= density of water
g=gravity
h= depth of water
dh= change in depth of water
A= area = width*h
D = depth (as defined by problem)
F=((atm) + pgh)*A
But because pressure changes with depth, we must integrate
dF = ((atm) + pgh) * (width*dh)
Integrating yields:
F= (atm)(width)(h) + (.5)(p)(g)(h^2) evaluated from 2D to 3D
Evaulating yields:
F= 3D^2((atm) + 1/5pgD) - 2D^2((atm) + pgD)
The answer that I get from this calculation does not agree with the correct answer; is there something I am missing?
Hi, I'm new to this site, so I'm not sure if this is the right place to post. I found a year-old entry with the same question that I'm having trouble with, found here:
https://www.physicsforums.com/showthread.php?t=153538"
For Part a, I followed the same method that PremedBeauty followed, but can't seen to get the correct answer. Is there a force that I am missing?
For Part b, I integrated to try and find the total force, but, once again, my answer comes out incorrect. My calculations for part b are below.
F=force
(atm)= atmospheric pressure (in Pascals)
p= density of water
g=gravity
h= depth of water
dh= change in depth of water
A= area = width*h
D = depth (as defined by problem)
F=((atm) + pgh)*A
But because pressure changes with depth, we must integrate
dF = ((atm) + pgh) * (width*dh)
Integrating yields:
F= (atm)(width)(h) + (.5)(p)(g)(h^2) evaluated from 2D to 3D
Evaulating yields:
F= 3D^2((atm) + 1/5pgD) - 2D^2((atm) + pgD)
The answer that I get from this calculation does not agree with the correct answer; is there something I am missing?
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