Calculating Gravitational Force with Universal Gravitation Formula

[uno]

At what center-to-center distance from the Earth would a 0.9 kg mass weigh 0.9 N?



I used equation g = GM/r^2 to get an answer of 8.17 X 10^-6 which is incorrect.

Am I using the correct formula? Thanks

 

[Rake-MC]

Well you know at this distance, F = m which implies a = 1.

Therefore use your formula like this: 1 = GM/r^2

G = 6.67E-11
M = 5.98E24
r = 6.37E6 + R
Where R is the distance from the surface of the Earth.

You are going to want your answer to be of an order of much, much greater than E-6

 

[uno]

I got it. Thanks for your help.