Ask a Physicist: Protons & the Strong Force

Oscar, from New Mexico, wants to know:"Electromagnetic repulsion is inversely related to the square of the distance between both objects. Shouldn't this mean that the integral of the force between two protons is infinite if the distance becomes zero? If so, why can protons collide?" Oscar, Great question! The short answer is that, when the distance between two protons becomes small enough, the nuclear strong force (which is attractive) becomes more powerful than the electromagnetic repulsion bet...