Investigate how the cross section of a wire affects the resistance in a circuit.
To investigate how the cross section of a wire affects the resistance in a circuit Introduction In metals, when the electron becomes detached from the outer shell of their parent atom, it is then able to move freely between the positive ions of the metal, which arrange themselves in a regular lattice. In pure metals, the structure can be represented like this: The electrons are moving at a very high speed randomly, with no pattern at all. = Positive ion = Electron The electrons in a pure metal move at a very fast speed randomly, with no pattern at all. Metals are the best conductors because the detached electrons create a huge flow of 'free' electrons that can be made to move by the push from the voltage, in a circuit. Voltage is what gives the energy to the electrons, which pushes them along the wire of the circuit. Metals are good conductors because their atoms are arranged in a regular lattice, so that when the electrons flow through them they have many straight paths to go through. If a positive ion collides with an electron, the electron will slow down and the positive ion will pick up some of its energy. When this happens often, there will be two effects: . The current will slow down. 2. The metal
The resistance of a wire depends on certain factors. Some of these variables are listed below: Length of wire Diameter of wire Temperature at which wire is at
Resistance of wires Aims To investigate how increasing and decreasing the thickness and length of a wire affects its resistance. Background Knowledge Resistance An electron travelling through the wires and loads of the external circuit encounters resistance. Resistance is the hindrance to the flow of charge. For an electron, the journey from terminal to terminal is not a direct route. Rather, it is a zigzag path, which results from countless collisions with fixed atoms within the conducting material. The electrons encounter resistance - a hindrance to their movement. While the electric potential difference established between the two terminals encourages the movement of charge, it is resistance that discourages it. The rate at which charge flows from terminal to terminal is the result of the combined effect of these two quantities. Resistance is measured in ohms and can be calculated by using the formula R = V/I. Possible Variables The resistance of a wire depends on certain factors. Some of these variables are listed below: · Length of wire · Diameter of wire · Temperature at which wire is at · The material of which wire is made out of. · The potential difference across circuit. · Cross sectional area ) Temperature When the temperature of a metal increases the resistance of that metal increases. This is because when the temperature increases the atoms of
Identification of an unknown test wireThrough the experimental determination of it's Resistivity, p.
AS PHYSICS COURSEWORK: "Identification of an unknown test wire Through the experimental determination of it's Resistivity, p" NISHIT GOPAL Mr Toor/ Mrs Poole Identification of an unknown test wire through the experimental determination of it's Resistivity, p Introduction The purpose of this experiment is to identify an unknown wire that has been used in the experiment. I will determine the unknown wire by working out the resistivity value of the wire. In order for me to work out the resistivity, I will first need to determine the following: * The resistance of the wire; * The cross-sectional area of the wire; * The length of the wire. I am going to use resistivity of the wire to identify it because the resistivity value of a wire only depends on the material of the wire, the area and the length of the wire will not affect the resistivity value of the unknown wire. Before I start the experiment I already know that as the wire gets thicker, the resistance of the wire decreases, we say that the resistance is inversely proportional to the cross-sectional area of the wire (R ? 1/A). The reason for this is because as the wire gets thicker, the free electrons have more room to vibrate and because of this increased space between the atoms, there would be fewer collisions between the free electrons and the positively charged metal ions, resulting in more electrons being
An investigation to see what factors affect how well a wire will conduct electricity.
Electric Current Flow in Wires I am going to carry out an investigation to see what factors affect how well a wire will conduct electricity. I am going to investigate the affect of resistance. The resistance is when electrons travelling through a wire collide with the atoms of the wire causing many collisions which slows the flow of electrons which finally causes the resistance. There are several factors that affect the resistance of a wire, the thickness, the length and what the wire is made out of. If the wire is thicker then there is more space for electrons to move, and there won't be many collisions with the atoms from the wire. The length will affect the resistance because the longer the wire the more the electrons will travel and the more collisions will occur therefore the resistance will increase. In my investigation I am going to see the affect of the length of the wire against the resistance. I predict that when the length of the wire increases the resistance will increase. I think this will happen because as the wire increases in length, the electrons travel more which means more collisions will occur making an increase in resistance. I also think my graph will show that when you double the length, the resistance will also double showing positive correlation. To carry out my investigation I will need a power supply, ammeter, voltmeter, crocodile clips,
Each region of the EM spectrum has different uses in everyday life. radio waves These are used for transmitting radio signals, phone signals and television
Task four The electromagnetic spectrum is the entire range of radiant energies or wave frequencies. There are seven main regions in the electromagnetic spectrum. These are: radio waves, microwaves, infrared, visible light, ultraviolet, x-rays and gamma rays. Each section of the EM spectrum has a different wavelength, these are shown in the table below Section of EM spectrum Wavelength (in cm) radio waves > 10 microwaves 0 --> 10 infrared 0 --> 10 Visible light 0 -->10 ultraviolet 0 --> 10 x-rays 0 --> 10 Gamma rays < 10 Each region of the EM spectrum has different uses in everyday life. radio waves These are used for transmitting radio signals, phone signals and television. Also stars and gases in space emit radio waves. Microwaves These are used for cooking, in our microwaves. They can also be used for communication. Infrared This is used for heating, night vision and in remote controls. Visible light This is the light that we see. It is emitted by everything. Ultraviolet Is emitted from the sun, it is what tans our skin. It is also used for sterilising, and in forensic science, to see things such as traces of bodily fluids, which are invisible to the naked eye. X-rays These are used for medical purposes in hospitals, to look at our bones. Gamma rays These are emitted by radioactive substances, and
How does the length of wire affect resistance?
Elizabeth Stephens 11N Physics Coursework How does the length of wire affect resistance? Aim To find out how changing the length of wire will affect the level of resistance when current flows through it. What is Resistance? Current is a flow of electrons. As they travel down a wire there is a force acting against them, this is Resistance. Resistance is caused by two factors even . Positive nuclei in the wire. The positive nuclei attract the negative electrons and deflect them from travelling in a straight line. This means the electrons travel a much larger distance to go the same length through the wire and take longer. 2. The vibration of the positive nuclei in the wire. The positive nuclei vibrate at any temperature above absolute zero. The vibrations mean the nuclei move around and this causes more frequent deflections. This makes the journey of the electrons slower. The longer the wire, the higher the resistance because there are more nuclei in the way. The higher the temperature the higher the resistance because the nuclei have the energy to vibrate more and therefore cause more deflections. The larger the cross section of the wire the lower the resistance because more electrons can pass through the wire in the same amount of time. What is Resistivity? Resistivity is a way of measuring the resistance in a material. To find the resistivity you have to find
Investigate how the resistance changes in a wire of different lengths.
Andrew The Resistance in a Wire 16th November Lightstone Variables: - There are many variables for this experiment: the material of wire, the voltage, the width of the wire, and the length of the wire. Factors to observe: - You could see how the temperature changes and how the resistance changes due to the variables. Aim: - to investigate how the resistance changes in a wire of different lengths. This means my variable will be the length and factor to observe will be the resistance. In order to make it a fair test, all possible variables (except the length) must be kept constant. If I change the material of the wire half way through, its structure might be different to the one used previously i.e. there might be more particles for the electrons to bump into, so there would be a sudden jump in resistance between the two. If I accidentally changed the voltage, by moving it either higher or lower, their would be more or less current passing through, that that of the rest of the experiment, so it wouldn't be a fair test of resistance and there would be large jumps in my measurements. Prediction: - Once my results have been collected, the graph will look like this: Resistance (ohms) Length (cm) The resistance of the wire will be directly proportional to the length, i.e. as the length doubles,
I am trying to find out what factors influence the energy change when metals are added to a metal salt solution.
Chemistry Coursework. What Factors Influence the Energy Change When Metals Are Added to a Metal Salt Solution. Skill P Planning Experimental Procedures. Aim. I am trying to find out what factors influence the energy change when metals are added to a metal salt solution. Introduction. The energy released when one metal displaces another can be used in industry, for example in the reaction of aluminium with iron oxide to weld rails together. Your task is to devise a plan to show how the temperature rise, and hence the energy change, is affected by adding different metals to copper sulphate solution. A suitable metal would be iron, which reacts according to the equation (Fe(s)+CuSO4(aq)?FeSO4(aq)+Cu(s)) Prediction. Prediction Graph. I predict that when we put a metal from the reactivity series, the higher it will be, the larger amount of energy will be given off. If the metal is very reactive, eg: magnesium, the temperature will rise more than zinc because the further away the electrons are from the nucleus and therefore the more reactive the metal is because the more unstable the metal is and it will give off more electrons more easily and therefore release more energy. In aluminium's case, it should be more reactive than zinc. Variables. Dependent Variable: My dependent variable is going to be the temperature because that is what I am going to measure throughout
In this experiment, I will be seeing if the length of a wire affects the resistance.
I this experiment, I will be seeing if the length of a wire affects the resistance. The key variables to look out for, they are: * The temperature * Material * Length of wire * Wire width (SWG) If the wire is heated up, the atoms in the wire will vibrate faster of their increase in energy. This will cause more collisions between the electrons and the atoms. The increase in collisions means that there will be an increase in resistance. As the atoms will collide more, the more time it will take for it to get to the end of the wire, as time will be wasted in collisions. The type of material will affect the amount of free electrons that are able to flow through the wire. As materials like copper are good electrical conductors, and allow atoms to flow easily, unlike nickel. If the length of the wire is increased then the resistance will also increase as the electrons will have a longer distance to travel and so more collisions will occur. If the wire width is big the resistance will decrease. This is because of the increase in the space for the electrons to travel through. It is like a corridor, the smaller it is, the more chance of you being crushed, whereas in a big corridor, you will have lots of room around you. The piece of wire I have chosen is Constantine with 30 SWG. RESEARCH When the electrons flow through the wire, the longer the wire is, the more energy it
I am going to build a sensor for a vehicle fuel gauge. It will sense how much petrol or water there is in the tank.
Physics Sensor Coursework- Water Depth Sensor (Fuel Gauge) Introduction I am going to build a sensor for a vehicle fuel gauge. It will sense how much petrol or water there is in the tank. I am going to do this experiment because it involves mechanical aspects as well as electrical, so I am not focusing just on one type of component. There are not many different ways of doing this, although to change a bit I can add a fixed resister to it, which can change the results, and I could also decide if I want to measure the voltmeter across the resistor, or the potentiometer, this can also change the results because it will either make the voltage start from high and decrease, or start from zero and go up. But I will stick with doing the experiment without a fixed resistor. I have followed advice, to make sure in the sensor is correct, and also to change anything which could cause problems. Although problems have still occurred such as the stability of the potentiometer, it wasn't stable enough and kept moving, this disturbed the readings, but I corrected the issue by adding blu-tack which secured it in place. I also had to replace some of the equipment which were damaged and made the results inaccurate. This sensor is used in transports such as cars, motorcycles, trucks etc. and is a very important component. Without it the driver would not know how much fuel is left in
