What is the Nuclear Force?
An absorption or emission of nuclear energy occurs in nuclear reactions or radioactive decay; those that absorb energy are called endothermic reactions and those that release energy are exothermic reactions. The best-known classes of exothermic nuclear change process are fission and fusion.
The strong forces of attraction (Nuclear binding Energy) which firmly hold the nucleons in the nucleus are known as nuclear forces. Nuclear interactions or strong forces or Nuclear forces are the forces that act between two or more nucleons. They bind nucleons (protons and neutrons) into atomic nuclei. The nuclear force is powerfully attractive force between nucleons at distances of about 1 fm (fm = femtometer = 1.0 × 10−15 metres) between their centers, but rapidly decreases to insignificance at distances beyond about 2.5 fm. At distances less than 0.7 fm, the nuclear force becomes repulsive force. This repulsive component is responsible for the physical size of nuclei, since the nucleons can come no closer than the force allows. The nuclear force is about 10 millions times stronger than the chemical binding that holds atoms together in molecules. This is the reason why nuclear reactors produce about a million times more energy per kilogram fuel as compared to chemical fuel like oil or coal.
Properties of Nuclear forces:
Nuclear forces are extremely strong.
Nuclear forces are attractive in character.
Nuclear forces are short range forces.
Nuclear forces do not depend upon the charge on the nucleons.
Nuclear forces are non-central forces.
Nuclear forces do not increase with the increase in the number of nucleons.
Nuclear forces are dependent on the spin of the nuclei.