(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Planet X has a radius double of Planet Y. Planet X also has a mass that is double planet Y. How do the surface gravitational fields of X and Y compare?

2. Relevant equations

g=GM/R

3. The attempt at a solution

So because were looking for the ratio of gx to gy, we can use the equation gx = n(gy) and say that n = gx/gy. So since Planet X has a radius double of Planet Y, we can say that Rx = 2Ry. Also we can say that Mx = 2My. So this turns out to be (2MyG/2Ry) / (MyG/Ry) = n. So this becomes 2MyGRy/2RyMyG = n. Cancelling out Ry, My, and G leaving 2/2 = n. This would say that gx = gy ? Does this make sense to say that at different masses and radii the planets have equal gravitational force?

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# Homework Help: The ratio between gravitational force of planet x and y

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