Weight of the Earth on the moon?

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cosmic_tears
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Hi everyone!
Ok, so here's the problem:
What would be the weight of the Earth if it were on the moon (just try and imagian that :). The masses of the moon and the earth, and their radiuses, are given.
I cannot see what's the trick here.
There are four possible options.
The one that seemed the most logical is :

(GmM)/(R+r)^2
where m - moon mass, M - Earth mass, R - Earth radius, r - moon radius.

But the material it's supposed to be related to is torques and moments of force... I don't see how it's related :-\

I'd be really thankful for help on how to approach this problem.

Thanks!
Tomer.
 
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Is it the same as the weight of the Moon on the Earth?
 
Weight = gravitational force between two object.

P.S. I wonder if the Earth is sitting on me, or I am sitting on the earth?
 
Thank you all!
I simply thought I'm missing something! I thought maybe I should somehow consider the fact that the far side of the Earth is much further away from the moon than the close side, (as opposed to now, when there's hardly any difference).
It made me think about the fact that if you walked into a black hole your legs will probably get torn cause of the different gravity on your body :).
Thanks again!