Force pressure variance after hole is plugged?

AI Thread Summary
The discussion centers on the force required to insert a plug into a gushing hole versus the force needed to maintain the plug's position once inserted. It is suggested that the initial force to push the plug into the hole may differ from the force required to keep it in place due to the dynamics of fluid pressure. Participants are encouraged to consider the principles of hydraulics, particularly how pressure changes when a hole is plugged. The conversation also hints at exploring real-world applications, such as hydraulic rams, to understand these forces better. Ultimately, the key question remains whether it takes more, less, or equal force to maintain the plug compared to the force needed for insertion.
tmalcolm
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TL;DR Summary
what is the force delta to plug a leak in a vessel vs the force to maintain the plug after it's in place?
There is a tall cylinder filled with water. And there is a 3 in diameter hole near the bottom and water is gushing out. (assume the cylinder is continually being re-filled from the top)

You work to plug the hole with a 10 inch long cylinder that is exactly the perfect diameter fit to plug the hole. (Assume a perfect fit with no wall friction as it slides into place)

It takes X amount of lbs of force to push the cylinder plug into the gushing hole to stop the leak.

Question -
How much force does it take to keep the plug in the hole once it has been pushed in vs the force required to get the plug in the hole initially?
(meaning, is it "easier" to keep the plug in the hole once it's inserted?) (equal to, less than, more than?)

Does it take more, less or equal force to push the plug deeper into the hole vs the amount of force to keep it one position?Thank you!

Tom
 
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tmalcolm said:
Summary:: what is the force delta to plug a leak in a vessel vs the force to maintain the plug after it's in place?

There is a tall cylinder filled with water. And there is a 3 in diameter hole near the bottom and water is gushing out. (assume the cylinder is continually being re-filled from the top)

You work to plug the hole with a 10 inch long cylinder that is exactly the perfect diameter fit to plug the hole. (Assume a perfect fit with no wall friction as it slides into place)

It takes X amount of lbs of force to push the cylinder plug into the gushing hole to stop the leak.

Question -
How much force does it take to keep the plug in the hole once it has been pushed in vs the force required to get the plug in the hole initially?
(meaning, is it "easier" to keep the plug in the hole once it's inserted?) (equal to, less than, more than?)

Does it take more, less or equal force to push the plug deeper into the hole vs the amount of force to keep it one position?Thank you!

Tom
Is this homework? What do you think the answer is/what have you tried?
 
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