Fluid velocity (Bernoulli's Principle?)

AI Thread Summary
The discussion focuses on calculating the velocity of a non-viscous liquid emerging from a hole at the bottom of a tank, given that the liquid's surface is 0.5 m above the hole. Bernoulli's equation is referenced, emphasizing that the pressure at the hole is atmospheric, allowing it to cancel out in the equation. The importance of treating the liquid as incompressible and non-viscous is highlighted, ensuring no frictional energy loss. Participants confirm the calculations and clarify that the final velocity should be expressed in meters per second (m/s). The conversation concludes with validation of the solution's correctness.
lifeiseasy
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Homework Statement


A wide tank contains a non-viscous liquid. The surface of the liquid is at a height 0.5 m above a hole situated at the bottom of the tank. Assuming streamline flow, calculate the velocity of the liquid emerging from the hole.


Homework Equations


P + 1/2 Dv^2 + Dgh = constant (?)


The Attempt at a Solution


h=0.5 m
non-viscous -> density unchanged
Then? I can't continue.
 
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Write out the constant side of Bernoulli's equation. It will describe the state of the water at the hole.

Hint: Since the water coming out the hole is coming into air the pressure on the water will also be atmospheric pressure (so it cancels from both sides).
 
"non-viscous -> density unchanged"

Non-viscous means moving without frictional energy loss. When the densy is unchanged, it is incompressible. In this problem you assume incompressible as well as non viscous.
 
Last edited:
Thanks AtticusFinch for your hints and Phrak for your correction (I just mixed them up). I think I've arrived at the answer.

Is it correct?
 

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lifeiseasy said:
Thanks AtticusFinch for your hints and Phrak for your correction (I just mixed them up). I think I've arrived at the answer.

Is it correct?

Yeah that looks correct to me. However you final units should be m/s
 
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