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1. The problem statement, all variables and given/known data

"Suppose that we could use the energy released

when 4 g of antimatter annihilates 4 g of

matter to lift a mass 1 km from the Earth’s

surface.

How much mass could we lift? Answer in

units of kg."

2. Relevant equations

e=mc^2

w=fd

f=ma

3. The attempt at a solution

I was attempting to find the energy with e=mc^2 and using .004kg as the mass. Then I tried using work(energy)=force*distance and force=mass*acceleration (using gravitational potential energy) but my answer was incorrect. For the record, i answered 3.67e10 kg but no luck. I'm stumped. :(

EDIT: I think the proper way is using the potential energy equation [energy=mass*gravity*height] after I have found energy from [e=mass*speed of light^2] Is this right?

Would the total energy released be from .004kg or from .008kg of matter?

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# Homework Help: Energy causing motion

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