Mars has a radius of about 0.38 Earth radius and a mass of only 0.11 Earth mass. Estimate the acceleration due to gravity on Mars.'

Answer 1

gravity proportional to mass, indirectly prop to square of radius.
First, the radius above is wrong. The mars radius is about .53 re, not .38

Forcegravity=GMm/r^2

gearth=GMe/re^2=9.8

gmars=GMm/rm^2

gmars=G.11Me/(.38re)^2=

gmars=.11/.38^2 *9.8 which is much more than what we find on Mars.