posted by Lindsay on .
Suppose that the ratio of the Moon's mass to the Earth's mass is given by 1.200E-2 and that the ratio of the Moon's radius to the Earth's radius is given by 2.700E-1. Calculate the ratio of an astronaut's Moon-weight to Earth-weight.
Now it seems like this problem really shouldn't be too difficult. However, I'm not sure of how to solve it given ratios instead of the actual masses and radius's.
Wm/We = gm/ge = (GMm/rm^2)/(GMe/re^2) or Mm(re^2)/Me(rm^2).
Right. But w/o knowing the actual mass of the earth and moon, only the ratio, how can I do this?
Lindsay, you are given Mm/Me, and rm/re
Wm/We= Mm/Me * (re/rm)^2
Ohhh I see now! Sorry, I just wasn't understanding before.