Today we will try to understand the forces that prevail our universe. In order to understand the forces of our universe, we must understand what makes up the universe. All around you can see the physical makeup of the universe – the mountains, trees, air, and water – all these are made up of matter. But what keeps the matter together? What prevents building and trees from floating off into space? What keeps the atoms of a molecule from falling apart? The answer is force. Understanding all of the forces involved in the universe is critical to understanding the universe as a whole. There are four known types of forces that interact with matter to define our universe. They are the strong, weak, electromagnetic, and gravitational forces.
Gravitational Force
Gravity is a force with which we interact every day. It is responsible for keeping your feet on the ground and for bringing a stone back down when thrown or hit. It is also responsible for keeping the moon orbiting around the earth in its orbit , the earth orbiting the sun, and keeping galaxies together and many other natural phenomenons that we observe in our day to day lives. Gravity is present wherever matter is present. But you will be amazed to know that despite having its influence so much, Gravity is the weakest of the four forces that prevail our universe . However, the more matter that is present, the stronger the gravitational force is. And gravity works over very great distances – trillions and trillions of miles. An individual atom however contains a very small amount of matter, and therefore the gravitational force from it is very tiny. A very large object, like the Earth, has an enormous amount of mass and therefore has a very strong gravitational force. It is the combined gravitational pull from all the atoms in the Earth that pulls you, the moon, and baseballs to the ground.
Weak Force
Despite the name, the Weak force is actually 10^34 (10 million trillion trillion trillion) times stronger than gravity. The weak force exists deep inside the nucleus, or center, of atoms. It is responsible for determining if an element will be a proton, electron, or neutron. The weak force has a very small range, so it is not visible in our every day lives . However, without the weak force, the universe could not exist as it does. To state its importance, its enough to say that without it, stars could not shine and elements heavier than iron would not exist.
Electromagnetic Force
The Electromagnetic force is also present in our everyday lives. The magnets on your refrigerator, engines in your car, and all electronic devices use Electromagnetic force. It is the second strongest of the four forces. The roots of Electromagnetism, like Gravity, can be traced to the atom. Atoms contain tiny particles that have a property called ‘charge’. There are two types of charge; ‘negative’ charge is a property of electrons, and ‘positive’ charge is a property of protons. The interactive force between these two charges is Electromagnetism. Opposite (that is, negative and positive) charges attract (or pull towards) each other, and like (that is positive and positive, or negative and negative) charges repel (or push away from) each other. This is different than Gravity, which always attracts. Like Gravity, many electrons together can combine to produce a strong negative electromagnetic force, and many protons together can combine to produce a strong positive electromagnetic force. The Electromagnetic force is about 1000 times stronger than the weak force. If you take a penny and separate its electrons from its protons, and put each half on opposite sides of the earth, the force between them would equal 120 tons! The force due to Gravity between them would be almost undetectable.
Strong Force
The center of an atom, the nucleus, is made up of protons and neutrons. Protons have a positive charge, and neutrons have no charge at all. This means that, in the nucleus, there are many positive charges sticking together. If you remember from Electromagnetism, like charges repel each other. What keeps the protons from flying apart? The answer is the ‘Strong’ force. The Strong force, as the name implies, is the strongest among all the forces. It is a very powerful force that binds the nucleus of an atom together. There is a large amount of energy stored in this force. This is where nuclear energy comes from. When an atom’s nucleus is split, the energy stored by the Strong binding force is released. This energy is then converted to electricity. A small amount of atoms contain a very large amount of energy stored in the Strong force holding the atom together.
Force Fields
All forces which act upon an object always act in a particular direction. For example, gravity pulls objects in a straight line towards the center of the object creating the gravity. Electromagnetic forces go from the positive charge to the negative charge (North Pole to the South Pole for magnets). The patterns created by these are called Force Fields. Basically, the lines in a force field describe how an object will move when placed near an object that emits a force.
Comments