Hypothetical Bernoulli situation with Pascals Law(Efflux torcellis result)

AI Thread Summary
The discussion centers on a tank with water draining through a hole at the bottom, utilizing Bernoulli's equation to determine the efflux speed of the water. The velocity at the bottom is calculated using the formula V = √(2 * gravity * depth). The question arises about the velocity of water at the top of the tank as it drains, with the application of Pascal's law to relate flow rates. It is confirmed that the flow rate out of the tank must equal the rate of change of volume at the top, indicating that the velocity at the top is indeed smaller than the efflux velocity at the bottom. This understanding aligns with the continuity principle in fluid dynamics.
jlyu002@ucr.e
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Homework Statement

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There is tank with a certain depth with water that is exposed to air. There is a hole at the bottom of the tank. Using Bernoulli's equation, we can find the efflux speed. density of the water * gravity * depth = 1/2density of water * velocity ^2.

This will give us the velocity of the water at the bottom of the tank which is V= Squareroot of (2*gravity*depth).

My question is now, what would be the velocity of the water at the top as it is draining. I believe we can use pascals law where Flow(area times velocity)= Flow2(area2 times velocity). Since the area of the top of the water is bigger, the velocity of the water at the top draining would be smaller than the efflux velocity?

Do I have the correct interpretation? [/B]
 
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Yes. The flow out of the tank at the bottom of the tank must equal the rate of change of the volume at the top of the tank, according to the continuity relation. As long as the area of the hole at the bottom is less than the area of the free surface at the top of the tank, then the time rate of change in water depth measured at the free surface must be less than the velocity of the water squirting out the bottom of the tank.
 
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Sweet! Thank you good sir!
 
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