Four Fundamental Forces
There are four fundamental forces that exist in nature. They are Gravitational force, Electromagnetic force, Weak nuclear force and Strong nuclear force. Among these forces Strong nuclear force is
Gravitational force is responsible for the structure of universe, cluster, galaxies and star formation.
The electromagnetic force is responsible for all the molecules and molecular interactions. EM force is responsible also for Shape and size of different objects on the earth, Radiation pressure of gases on the star and for the stability of any star or system.
Muscular force, contact force between bodies, friction, the force exerted by spring and ropes, viscous force, buoyant force are the example of electromagnetic force.
Weak Nuclear Force:
Weak nuclear force gives the limit of nuclear size and
Strong Nuclear Force:
The strong nuclear force binds protons and neutrons inside the nucleus. It is proved that without some attractive force, a nucleus will be unstable due to the electric repulsion between the protons. This force of attraction cannot be gravity because gravity is a very weak force
The strong nuclear force is strongest among all four fundamental forces. It is about 100 times stronger than the electromagnetic force and independent of charge like gravity. It acts equally between proton and proton, and neutron and neutron, and proton and neutron.
Recent developements in the nuclear theory proved that proton and neutron are built by more elementary particles known as quark. Unification of all four fundamental forces is a basic quest in physics. Einstien attempted to unify gravity and electromagnetism but could not succeed in this venture
Recent decades have seen much progress on this front. The electromagnetic and weak nuclear forces have now been unified and are seen as