Explain why for heavy nuclei there is imbalance in the number of protons and neutrons. Give reference to the range and particle type of the forces that influence this imbalance.

In the nucleus the forces that govern how the body is kept together is the Strong Nuclear Force and the Electromagnetic Force, these two force differ in range and the type of particle they interfere with. The Strong Nuclear Force affects baryons and as such both protons and neutrons are bound when they are within the range dominated by the force, this is around 3fm. If these nucleons are bound closer than 0.8fm thy will feel repulsion, the result of this means that the nucleus cannot collapse in on itself and that the nucleons may only be tightly bound to a degree. Protons and neutrons are bound in the nucleus governed by the Strong Nuclear Force, instability arises from the Electromagnetic Force governing proton-proton interactions, causing repulsion. The neutral charged neutrons do not feel the Electromagnetic force, which acts across the whole of the nucleus and are as such unaffected by the force. In order for a large nucleus to be stable fewer protons are required to reduce the repulsion in the nucleus and ensure its stability.