Energy/rotational mechanics question

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The discussion revolves around a homework problem related to energy and rotational mechanics, specifically involving a solid sphere rolling without slipping. Key points include the identification of gravitational potential energy (Ug = Mg(y - a)) and the need to consider rotational kinetic energy due to the sphere's moment of inertia. Participants emphasize the importance of understanding the relationship between different forms of energy in the context of rotational motion. The original poster expresses confusion about these concepts and seeks clarification on how to approach the problem. Overall, the thread highlights the complexities of rotational mechanics and the need for a clear understanding of energy types involved.
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Homework Statement


Check attached image.

Homework Equations


The rotational motion formulas
Ug = mgh


The Attempt at a Solution


Have no idea unfortunately :(
 

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List the types of energy that will be involved and their basic formulas.
Are there any relationships between these energies? (hint: consider that the sphere is rolling without slipping).
 
OK, so kinetic energy and gravitational potential energy.
I got the first part correct, Ug = Mg(y - a)
but the 2nd part... not so much :\
 
You've missed out an important form of energy. Why do you suppose the problem gives you the expression for the moment of inertia of a solid sphere?
 
Rotational kinetic energy?
Sorry, I'm really lost when it comes to rotational mechanics, I need people to spell it out for me :(
 
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