Resistance of a Wire Essay Example for Free

Resistance of a Wire Essay Will changing the length and type of wire affect the resistance? What is my aim of this project: To set up an electric circuit to measure the resistance of the wire. What are my Variables:   Nichrome coil What is resistance? Resistance is measured in (OHMS). It is the hindrance to the flow of charge. Why did we get resistance? An electric current flows when electrons move through a conductor. The electrons that are moving can collide with the atoms of the conductor. This then means that it is more difficult for the current to flow, which causes resistance. On the other hand, electrons have a collision with atoms more often in a longer wire than they do in a short one, however, a thin wire has fewer electrons to carry the current than a thick wire. In a thin wire there is less space, but more resistance and in a long wire there is more space, yet less resistance. The flow of electrons: Hypothesis: Before I do my experiment I predict that the resistance in the wire will increase as the length of the wire increases. I also predict that if the resistance in the wire increases, then the thickness of the wire will decrease. My diagram of my circuit: For my first investigation task I will be doing a preliminary test to find out which are the best wires to use for my investigation. This task was completed and threw my results I realised that using the Nichrome would be better for my investigation. This is what was done before the main experiment. Preliminary test: Length Apparatus Test1 Test2 Test3 Test4 Average Resistance 10cm Ammeter   The graph shows that the data is positive.  From observing this graph above I can see that my data is close fitted along my line of best fit and that the data increases a lot, showing that this is a . as well as this there is s apiece of anomaly data, which is my outlier, circled in black. For my experiment, I will be taking account the differences in resistance between the different lengths of Nichrome wires. This will be tested against copper which, has a low resistance and high current and is thinner than the Nichrome wire that has high resistance and low current. Method. In order for me to complete my investigation, I will need to gather the equipment listed above and set up my electric circuit. This will be done by the use of connecting my wires to the volt meter and ammeter and then attaching crocodile clips on each ends of the wires. It is necessary for the wires to be in this position, as the crocodile clips play an important role in griping the coil firmly whilst the investigation takes place. After doing this I will cut the chosen coil to the measurement I desire. These measurements will be of 10cm, 20cm, 30cm, 40cm and 50cm. With these different measurements, I will attach the coil to the circuit to make it complete. Then, I will turn on the power pack and take down the readings from the voltmeter and ammeter, reading off the voltage and current. From these readings, I will calculate the resistance and average. My results from my readings will be presented in a table. With this experiment, I will keep all the equipment the same however my variables will be the type of wire, the length and the thickness. Repeating my test makes my investigation more reliable. Temperature is a factor that affects the resistance. For each reading I take I will switch off the power pack between each test, making my investigation much more reliable. Below are my table results for Nichrome wire Test (1) The wires length (cm) Voltage (V) Current (A) Resistance (? ) Below is my graph on my results From my line graph I created, I can see that my readings from each test were very alike for each time the experiment was being done. From looking at my results in the graph, there were no outliers. However, it also shows that my hypothesis predicted was correct, because the longer the wire was the more resistance there was it had a low current and a high resistance. Evaluation: I think my investigation worked well against my method and my hypothesis. I was able to complete my aim of this investigation, which enabled me to take down my readings of the current and voltage easily. I found the circuit easy to manipulate with no obstructions, which enabled me to record my results accurately for the resistance of the different lengths of wires. If I had the chance to re-do this project, I would have used a smaller current, because then I wouldnt affect the wires temperature in heating. This would then mean that it wouldnt affect the resistance of the wire being tested. As well as this I would use longer measurements of wire instead of just testing up to 50cm and test more different types of wires. Lastly, I feel that my experiment went well, which achieved its aim. Show preview only The above preview is unformatted text This student written piece of work is one of many that can be found in our GCSE Electricity and Magnetism section.