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**1. Homework Statement**

A water storage tank is open to air on the top and has a height of 1 m. If the tank is completely full and a hole is made at the center of the wall of the tank, how fast will water exit the tank?

**2. Homework Equations**

Pressure is the same as atmospheric pressure because the tank is open to the air. Also, linear flow speed at the surface is essentially zero, so...

Bernoulli's equation can be simplified to:

rho * g * h1 = 1/2 * rho * v2^2 + rho * g * h2

**3. The Attempt at a Solution**

rho= density

g= 10 m/ s^2

height 1 (or height initial)= 1 m

Here is where I don't understand the solution...

height 2 is apparently = 0.5 m, but this is not in the question stem....

rho * g * h1 = 1/2 * rho * v2^2 + rho * g * h2

My attempt at solving for v2 ultimately comes out to be:

v2= sq rt 2g (h1-h2)= sq rt 2* 10 m/s * (1 m - 0) = sq rt 20 meters

But the correct way to solve was:

v2= sq rt 2g (h1-h2)= sq rt 2* 10 m/s * (1 m - 0.5 m) = sq rt 10 meters

So, I guess my question is why would the final height (height 2) be 0.5 m?

Or, is there any other way to get the correct answer of sq rt 10 meters?

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