In my physics class, we did a free fall lab where we had three different balls dropped from different heights. The balls were of varying masses--a steel ball, a golf ball and a hollow plastic ball. Now I'm asked why the acceleration due to gravity is less for the plastic ball than the others. I have to explain why I think the plastic ball would behave like this and the other balls would not. I think it has to do with the force and mass. I know acceleration is independent of mass, but the hollow plastic ball has less mass compared to the steel and golf ball, thus less force is acted on it. I don't think my physics professor would think this is a legitimate answer though. I'm actually sort of confused whether he is convinced that somehow acceleration due to gravity is different for the lighter ball or it's some kind of trick question.I would greatly appreciate is someone could confirm what I think or correct me if I'm wrong. Thanks!