Modeling Kinetic Energy of a Ball Roll Experiment

AI Thread Summary
The discussion focuses on modeling the kinetic energy of a ball rolling from a height, emphasizing the relationship between potential energy (PE) and kinetic energy (KE) as described by the equations KE=PE and 1/2mv^2=mgh. Participants clarify that the experiment demonstrates how gravitational potential energy converts to kinetic energy as the ball descends. The initial work done to elevate the ball is acknowledged, but the primary interest lies in the gravitational field's conservative nature. Ultimately, the experiment serves to illustrate the conversion of potential energy to kinetic energy at the moment of impact. The conversation concludes with a confirmation of understanding regarding the experiment's purpose in calculating kinetic energy.
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Homework Statement


explain how an experiment where you let the ball roll from a certain height only models dropping a ball and finding its kinetic energy just as it hits the ground


Homework Equations


KE=PE
1/2mv^2=mgh

i don't think you need to utilize these equations


The Attempt at a Solution


i think since you already do work on the ball by putting it at a certain height and allowing it to roll down, there is no potential gravitational energy and since it is going to the ground, it is gaining kinetic energy, therefore kinetic energy can be found
 
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First of all of course there is gravitational potential energy. Whatever the work that got the ball there isn't really of concern.

What is of interest though is the conservative nature of a gravitational field. Perhaps you should explore that for a moment?
 
You are correct

edit: @ Lowly
 
so since you start out with a set amount of potential energy from the work done on the ball, the only thing the experiment is helping you find is the kinetic energy of the ball

is this how i could answer the question
 
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