Deriving a formula for Kinetic Energy

AI Thread Summary
The discussion revolves around deriving a formula for kinetic energy (Ek) related to a ball's motion, with confusion regarding the height (h) and the energy being analyzed. Participants emphasize the need for clarity on whether h refers to the ramp's height or the total height from the ground. There are questions about whether the kinetic energy in question is at the point of leaving the ramp or upon impact with the ground. Additionally, the importance of including attempts at solving the problem is highlighted, as well as the relevance of concepts like moment of inertia and rotational kinetic energy. Clear articulation of the original question and any diagrams is also encouraged for better understanding.
Vince716
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Homework Statement
A ball is rolled off the top of a ramp, onto the ground. Derive the following formula for kinetic energy by any means possible:
Relevant Equations
Ek=gmR^2/4h
I have no idea how to do this. I've tried conservation of mechanical energy and it didn't work.
Ek = Kinetic Energy
R = horizontal range of the ball
h = height from which the ball is released
 
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Forum policy requires you to provide your own attempt. If you can’t solve it, what have you thought about? What concepts do you believe are relevant?
 
There are some ambiguities in the problem statement.
Is h the height of the ramp from bottom to top, the height of the bottom of the ramp from the ground, or the sum of the two?
Is the energy in question the KE as it leaves the ramp, the KE as it hits the ground, or the difference of the two?

As @Orodruin asks, please post your attempt, regardless of its failure.
 
In addition to what @Orodruin and @haruspex have said, may I ask: have you learned about moment of inertia and rotational kinetic energy yet?

If the answer is ‘no’ (which I suspect is the case), then I think you have stated the question (very) wrongly!

(Edit: If you have learned about rotational kinetic energy, is 'Ek' the translational or total kinetic enery?)

Check you have posted the original question, word-for-word, and include any diagram supplied.
 
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