Lab Report: Testing How the Length of a Wire Determines its Resistance :: essays research papers

Science CourseworkThe opposition of a WireAimTo find out how the length of a wire affects the resistance of it.KnowledgeOhms justness is a mathematical comparison that shows the relationship between Voltage, Current and electrical resistance in an electrical circuit. It is say as&61623, V = I x R &61623, R = V / I &61623, I = V / RWhere V = Voltage I = Current (I stands for INTENSITY) R = Resistance In order to understand what Ohms Law is alone about you need to understand electricity and what makes Voltage, Current and Resistance in a circuit.CurrentCurrent is the movement of electrons in a circuit but What are electrons and what makes them move? All matter is make up of Atoms. Piece of metal made up of AtomsEach subatomic particle is made up of a nucleus that has a certain itemize of protons and neutrons with an equal numbers of electrons in orbit.The copper atom has 29 protons in its nucleus with 29 electrons orbiting the nucleus. The electrons are arranged in orbit s called crustal plates. Notice that in the copper atom, the outside shell has only wiz electron. The outer shell of whatsoever atom is called the valence shell. When the valence electron in any atom gains sufficient energy from some outside force, it can ramify away from the parent atom and find what is called a free electron.It is very(prenominal) easy to provide enough energy to cause the valence electron to become free. Some sources of energy are heat, light, magnetic fields and a voltage source. When the valence electron becomes free it leaves behind an atom that has a positive charge. Remember that the copper atom has 29 + protons and 29 electrons so if peerless electron leaves orbit we are left with +29 protons and 28 electrons. That means the atom has a more positive charge because of the one less electron. This is an unbalanced atom and is not natural. The atom will invariably turn up to get an electron back into the valence orbit to become normal or balanced again . This is the one fact that you should remember and try to visualize when working with electrical circuits. Electric current is the movement of electrons from one atom to another in a conductor. If you can visualize a piece of copper wire with billions of atoms and each one of them losing an electron and all the electrons jumping to other atoms, you will begin to see what current is.