#### Eunos_Cosmo

##### Forum Addict

- Joined
- Oct 7, 2007

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- 6,968

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- '84 Mazda RX7, '12 Mazda 2, '99 Porsche Boxster

So I'm sort of struggling with this problem, anyone have some helpful ideas on what to do?

"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."

I was attempting to find the energy with e=mc^2 and using .004kg as the mass. Then I tried using work(energy)=mass*gravity*height to arrive at a mass, but my answer was incorrect. When I use .004kg for mass, I end up with 3.67e10, which isn't correct. Anybody got any ideas?

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?

Cmon...I know there are some Germans on here!

"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."

I was attempting to find the energy with e=mc^2 and using .004kg as the mass. Then I tried using work(energy)=mass*gravity*height to arrive at a mass, but my answer was incorrect. When I use .004kg for mass, I end up with 3.67e10, which isn't correct. Anybody got any ideas?

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?

Cmon...I know there are some Germans on here!

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