A spaceship of mass m travels from the Earth to the Moon along a line that passes through the center of the Earth and the center of the Moon.(adsbygoogle = window.adsbygoogle || []).push({});

At what distance from the center of the Earth is the force due to the Earth twice the magnitude of the force due to the Moon?

r = ? m

I'm thinking of using the F = Gm1m2/r^2 with G being the gravitational constant and m1 being the mass of the earth, and m2 being the mass of the moon. but i don't know why they say "spaceship of mass m" or if that's even the proper formula to use???

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# Homework Help: Physics problem involving gravity?

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