How Fast Does Water Exit a Hole in a Tank?

AI Thread Summary
The discussion revolves around calculating the speed and diameter of water exiting a hole in a large storage tank, with the hole located 16.0 meters below the water level. The flow rate from the leak is given as 2.50 x 10^-3 m^3/min. Participants note that Bernoulli's equation can be applied, assuming negligible velocity at the top of the tank and atmospheric pressure at the hole. The importance of recognizing atmospheric pressure at the hole is highlighted as a key factor in the calculations. Ultimately, understanding these principles is essential for accurately determining the water's exit speed and hole diameter.
Gear300
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Heh...this question actually looks as simple as hell (and it probably is)...but there always seems to be one variable missing:

A large storage tank, open at the top and filled with water, develops a small hole in its side at a point 16.0m below the water level. if the rate of flow from the leak is equal to 2.50 x 10^-3 m^3/min, determine (a) the speed at which the water leaves the hole and (b) the diameter of the hole.

I'm assuming that the storage tank is much bigger than the area of the hole, so the velocity of the water at the top is negligible...and the pressure there could be taken as atmospheric pressure (its open at the top). I could then use Bernoulli's equation but I seem to be missing the pressure at the point of leakage and I don't think that Pascal's equation would work due to the fluid retaining a velocity at that point.
 
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Hi Gear300,

Gear300 said:
Heh...this question actually looks as simple as hell (and it probably is)...but there always seems to be one variable missing:

A large storage tank, open at the top and filled with water, develops a small hole in its side at a point 16.0m below the water level. if the rate of flow from the leak is equal to 2.50 x 10^-3 m^3/min, determine (a) the speed at which the water leaves the hole and (b) the diameter of the hole.

I'm assuming that the storage tank is much bigger than the area of the hole, so the velocity of the water at the top is negligible...and the pressure there could be taken as atmospheric pressure (its open at the top). I could then use Bernoulli's equation but I seem to be missing the pressure at the point of leakage and I don't think that Pascal's equation would work due to the fluid retaining a velocity at that point.

When the fluid stream is actually touching the atmosphere, it will have atmospheric pressure.
 
O_O...oh...well that's something...its a hole after all...heh, thanks for the help.
 
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