Find the force of attraction on a 3 kg mass at the surface of a planet given the following information about the planet:

mass = 5.98 x 10^24 kg, radius = 6.38 x 10^6 m.

Find the force if the radius is doubled to 12.76 x 10^6m

Thanks!!

3 answers

F = G m M /r^2
where
G = 6.67 * 10^-11

If you double the radius, you divide the force by 4 (1/2*1/2) = 1/4

29.4 N

for part b
7.35 N