Hydrostatic pressure forces and torque

AI Thread Summary
The discussion centers on calculating the torque on a rectangular gate at the top of a dam, which is 4 m wide and 3 m tall, with water at a level of 8 m above its edge. Participants express confusion about how to approach the problem and the relevance of the gate in the context of hydrostatic pressure. There is a request for clarification and assistance, emphasizing the need for a diagram to better understand the scenario. Some contributors believe the problem is appropriate for an introductory physics course, while others suggest it may require more specialized knowledge in fluid mechanics. The conversation highlights the importance of visual aids in solving complex physics problems.
Dr_bug
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Homework Statement


Consider the dam in example 3. Suppose there is a rectangular gate near the top of the dam that can be used to release water. The gate is 4 m wide and 3 m tall and is hinged at its top edge so that it will close under its own weight. Determine the torque on the gate for rotation about its top edge when the water level is 8 m above its edge. see attachment for picture from example 3.


Homework Equations


Fℓ=(pgh)*(w dh)*(d-h)
w=sh +b
τ=∫[(pgh)*(sh +b)*(d-h)]dh-------going from 0 to d

The Attempt at a Solution


I'm having trouble getting started on this problem because i don't see how the gate fits into the picture. I'm not really understanding what they are asking. I would really appreciate any help at all... explanations of what I should do...
 

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Sorry if this doesn't help you but I think this question might be better placed in the engineering section. A fluid mechanics specialist would be able to help you out for this. I may just be tired but I believe this is beyond what I've covered so far in that subject.
 
okay I'll try...its just that this is an intro physics course and i didn't think about putting it elsewhere
 
I don't think it's beyond introductory physics, and what the OP did is probably on the right track. Do you have a diagram though, Dr. bug? It's kinda confusing without one.
 
oh yeah sorry i removed it when i reposted on the other page i'll put it back
 
okay i re-uploaded figure
 

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