1. The problem statement, all variables and given/known data Centre of gravity - the point at which: 1) gravity acts on a body or 2) weight of a body may be considered to act. The answer is 2) and I understand why - because gravity acts all over but it is easier to calculate a single point, an average point of where the mass is located. My question is, gravitational force and weight seem to be the same thing, so why does the question use different terminology? Is there actually a difference they are trying to express? Not that I think it's relevant to answering the question but does make me wonder why they are doing that.