# Homework Help: Conservation of energy relativity problem

1. Apr 14, 2004

### hibiscus23

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?

2. Apr 14, 2004

### Tom Mattson

Staff Emeritus
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.

3. Apr 14, 2004

### hibiscus23

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?

4. Apr 14, 2004

### JJ

You use mc^2=Mgh. mc^2 is still energy.

5. Apr 14, 2004

### Tom Mattson

Staff Emeritus
Is that the most famous equation in all of physics?

Nooooooo

C'mon, think Einstein.

6. Apr 14, 2004

### hibiscus23

thanks...i actually realized how to do it when i looked through the chapter again...