Question

What would be the acceleration of gravity (in m/s2) at the surface of a world with nine times Earth's mass and three times its radius?

Answer 1

Step-by-step explanation:

Given:

M = 9*M₃

R = 3*R₃

g₃ =9.8 m/s²

_______

g - ?

g₃ = G*M₃ / R₃²

g = G*M / R² = G*9·M₃ / (3*R₃)² = G*9·M₃ / (9*R₃²) = G*M₃ / R₃² = g₃

Accelerations are the same