I Need to Find the Acceleration Due to Gravity on an Unknown Planet

Question

On Planet X, the gravitational field strength is 5.43 N/kg. Planet Y is four times more massive and has three times the diameter of Planet X. What is the magnitude of the acceleration due to gravity on Planet Y (in m/s2 )

Answer 1

To find the strength of the gravitational field, we can use the formula:

g(r) = GM_planet/r² where r is the radius of the planet and M is the mass of the planet. On Planet X, we know that g(r)=5.43N/kg = GM_x/r_x²

M_y=4M_x and r_y=3r_x, so using this information, we can use the value of g on Planet X to determine what the value of g would be on planet y.

Note: N/kg is eq to m/s²