How fast was the ball moving when it left the pool table?

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The discussion centers on calculating the speed of a pool ball when it leaves a table, given its mass and the speed at which it hits the floor. The user applies the conservation of mechanical energy theorem, setting up the equation to relate the initial kinetic energy and potential energy to the final kinetic energy. They derive the equation and calculate the initial speed to be approximately 4.17 m/s. The user expresses uncertainty about the formula's applicability, indicating they will seek clarification in future discussions. The conversation highlights the importance of understanding energy conservation in solving physics problems.
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HELP! PlEaSe

Okay, here is my problem: In a wild shot, Bo knocks a pool ball of mass of .85 kilograms offa 95-cm high pool table, and the ball hits the floor with a speed of 6.0 m/s. How fast was the ball moving when it left the pool table?
I don't want to know the answer, I just want to know how to solve the problem, but I have no clue where to start. If someone could just help me get the problem started, or in the right direction, I would really appreciate it. Thanks!
 
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i used the conservation of mechanical energy theorem...

<br /> \frac{1}{2} (0.85)v^2 + (0.85)g(0.95) = \frac{1}{2} (0.85)(6)^2<br />

...

<br /> v^2 + 2g(0.95) = 36<br />

...

<br /> v^2 = 36 - 18.62<br />

so...

<br /> v = 4.16893272<br />

Well - if u find any mistakes - pls feel free to comment.
 
I saw that formula in my physics book, but I wasn't sure if it would apply to the problem because we haven't really gone over it yet.
But I'm going to use it to solve the problem, because it is a lot more than I had, and I will ask about it tomorrow.
Thanks!
 
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