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THE FUNDAMENTAL FORCES OF UNIVERSE

BY

FOAAD AHMED TAHIR

All things that we observe in our universe can be explained on the basis of physics, laws. Everyday observations from the running of automobiles to themovement of planets in orbits and the burning of stars occur because of the

presence of forces between matter. The universe consists of matter andenergy and they interaction of matter occurs in the form of forces whichleads to the presence of energy. These interactions occur because of theforce carrying particles. There are four fundamental forces in the universe,namely the strong nuclear force, the weak nuclear force, the electromagnetforce and the force of gravity. Combined these forces are responsible for theworkings of this universe.

THE STRONG NUCLEAR FORCE:

The strong nuclear force is responsible for the binding of the nuclei ofatoms. It has a very short range and thus its effect is only felt within thenucleus. It is transmitted via force particles called gluons which bindtogether uarks that leads to the formation of protons and neutrons and

cumulatively the nucleus. It is the strongest force of all and is !"" timesstronger than the electromagnetic force. #ut due to its small range it does not play a ma$or role in our everyday lives .

THE ELECTROMAGNETIC FORCE:

The electromagnetic force plays a dominant role in our everydaylives. The atoms and molecules within an ob$ect are held together only

because of these atoms. %ur machineries such as car engines, maglev trainsand other e uipment cannot work without it. It is also a strong force. It actsonly between charged particles such as proton and electron. This interactionoccurs because of the force particles photons. The electromagnetic force isuni ue in the sense that not only can it interact directly between matter butcan also travel in the form of electromagnetic waves thus enabling us totransmit information via it. It is a long range force as it varies inversely withs uare of distance.

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THE WEAK NUCLEAR FORCE:

This force is responsible for the disintegration of nuclei. It is again ashort range force and its effect is limited only within the nuclei. It istransmitted via &',&( and ) % particles. It plays part in phenomenon such asradioactivity and nuclear fission and fusion. It is a very weak force and ismillion times weaker than electromagnetic force. *et its role is decisive asthe stars would cease to burn without it.

THE FORCE OF GRAVITY:

The force of gravity plays also plays a very important role in our livesas the orbit of planets, formation of stars and our daily routine activitiesdepend upon it. It is a very weak force and is !"" million billion billion

billion times weker than electromagnetic force. +owever it plays the mostdominant role in the universe due to the fact that it is always cumulative,unlike electromagnetic force which is both attractive and repulsive. Thus dueto accumulation of matter its effect increases drastically. Infact so great is its

power that when a star explodes and if it has a critical radius then matter issucked and compressed due to its own gravitational attraction and eventuallyso much mass is confined in such a small space that the resultinggravitational field is strong enough to prevent light from escaping it. uch a

phenomenon leads to the birth of black holes. -ravity is caused by thehypothetical field particles dubbed gravitons, though they have not been

practically observed. In the time before " th century the concept of gravitywas that of /ewton, that an ob$ect creates gravitational field around it withwhich another ob$ect interacts leading to an attractive force. Though thistheory was very successful and predicted many things, including orbits of

planets, but still there were some observations unexplained by it. +oweverin !0!1 Einstein presented his general theory of relativity in which he

presented a totally new theory for the explanation of gravity whichexplained the previously unexplainable phenomenon such as shift inapparent position of star and the rotation of axis of 2ercury3s orbit. It stated

that gravity is a result of the distorting of space(time where a massive ob$ectis placed. Thus when any ob$ect is traveling in space(time it follows thedistortion and we observe it as an orbit. It can be visuali4ed as a heavyob$ect placed on a rubber sheet causing it to sag more at places near it, andless farther away. Thus according to this theory even light bends as it passesnear a massive ob$ect. Another remarkable conclusion of this theory is abouttransmission of gravitational changes. /ewton said that changes in

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