1. The problem statement, all variables and given/known data This is from Advanced Physics by Adams and Allday. Spread 8.26, Q 2. a) The strong nuclear force cannot fall off as an inverse-square law. Why not? b) Give a reason for thinking that the strong nuclear force must become a repulsion at very short range. 2. Relevant equations Non identified. 3. The attempt at a solution I have searched the Internet for phrases in the questions and found nothing satisfactory. The text book mentions quarks but nothing of colour, up/down, or mesons so I'm guessing the answers don't require that level of theory. For a) the expression "fall off" must mean reducing from a maximum ... For b) it seems simplistic to say the nucleons can't touch.