Starship + 2 different planets???? 1. The problem statement, all variables and given/known data The problem from my textbook is: Inside a starship at rest on earth, a ball rolls off the top of a horizontal table and lands a distance D from the foot of the table. This starship now lands on the unexplored Planet X. The commander, Captain Curious, rolls the same ball off the same table with the same initial speed as on earth and finds that it lands a distance 2.76D from the foot of the table. What is the acceleration due to gravity on Planet X? 2. Relevant equations The 4 basic equations of motion: V=Vi + a x delta t S=Si + Vi x delta t + 1/2at^s S=Si + 1/2(V+Vi)delta t V^2= Vi^2 + 2a(S-Si) 3. The attempt at a solution I know the initial velocity is the same in both cases, I figure you have to substitute the initial velocity in one with an equation with the acceleration on earth. I'm kind of lost from this point. What I really need is some one to explain how to solve it.