Why is the answer to gravitational potential energy question C?

Thread starter jack1234
Start date Nov 5, 2007
Tags

Energy Gravitational Gravitational potential Gravitational potential energy Potential Potential energy

AI Thread Summary

The discussion centers on understanding why the answer to a gravitational potential energy question is C. A user seeks clarification on the calculation involving the gravitational potential energy of a cubical block, specifically considering the center of mass. They propose a formula, 3m*g*(3/2 l)=9/2mgl, to calculate the potential energy, attributing the height to the center of mass being at 3/2 l. The conversation emphasizes the importance of correctly identifying the center of mass in such calculations. Overall, the focus is on clarifying the reasoning behind the gravitational potential energy answer.

Nov 5, 2007

jack1234

The answer is c, but I can't figure out what is the reason, can somebody kindly explain it?
http://tinyurl.com/32322t

Last edited: Nov 5, 2007

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Nov 5, 2007

Sourabh N

What do you think about gravitational potential energy of a cubical block?

Nov 5, 2007

jack1234

I am thinking about centre mass...
So what I am figuring is
3m*g*(3/2 l)=9/2mgl...(3/2 l because the centre of mass is at that height)
Is it correct?

Nov 5, 2007

Sourabh N

perfect.

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