Conservation of energy relativity problem

AI Thread Summary
The discussion revolves around a physics problem involving the conservation of energy and mass-energy equivalence. Participants clarify that the energy obtained from converting 5 grams of mass can be equated to gravitational potential energy using the formula E=mc^2 and Mgh. There is some confusion regarding the use of kinetic energy formulas, but it is established that the correct approach is to use mass-energy equivalence. The original poster ultimately finds clarity after reviewing their textbook. The conversation highlights the importance of understanding fundamental physics equations in solving energy-related problems.
hibiscus23
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Hi could someone please help me with this question. I don't know where to start. :rolleyes:

A certain amount of energy is obtained from conversion of 5.00 grams of mass. How much mass could this energy raise to a height of 96 m?
 
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Hi,

Use conservation of energy. The energy produced in the conversion (which you can caluculate by the most famous equation in physics) is equal to the gravitational potential energy. The only thing you don't know is the mass of the object that is raised to 96m.
 
um...

so it's 1/2mv^2 = mgh?
how would i get v?

If i use conservation of energy, then I don't have to use E=mc^2?

:confused:
 
You use mc^2=Mgh. mc^2 is still energy.
 
hibiscus23 said:
so it's 1/2mv^2

Is that the most famous equation in all of physics?

Nooooooo

C'mon, think Einstein.
 
thanks...i actually realized how to do it when i looked through the chapter again...
 

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