The resistance of a wire at different stages - Sample Essay
This is the stage where I have completed my experiment. I now want to talk about my work and mention how I did my works. This stage is important because I need to compare of how I said I would do the experiment to how I did do the experiment. A recap of the apparatus I used are listed below (for the main experiment) Constantan wire This is how exactly I did my experiment. I first cleared my table from all the unnecessary books, and then got all my apparatus out which I was going to work on.
I simply then started to make my circuit. I was very careful when plugging the power supply in, ensuring that the health and safety of my group was never in risk. Then once the equipment was set up, I started to test my experiments. I got different wires and cut them into different lengths, and then placed both ends on to the crocodile clips, and then I switched on the power supply, and quickly before the power supply was over heated I read the readings off the volt meter and the ammeter. I did this for both my variables, which is important. I kept the whole experiment the same, this was important for the test to be a fair test.
I can say that my experiment went very well; I think I did everything fairly and accurately. I can also add the fact that me or any of my group, led the whole experiment safely, and did not break anything and altogether very focused and that is why we have very accurate results. We worked together all the way. Before we started the tests, I had blank tables ready so all I had to fill out was the digits. This was very helpful, as it saved time. I have listed below the results that I obtained; these results were obtained from first hand, and all in the class.
The results are for both variables, and are indicated very clearly, which is for which variable. Also below that I have added a few explanations to help you understand the recordings. I will also like to add, that when I worked out the resistance, I used the formula: Resistance = Voltage/ Current. All working out has been rounded off to three significant figures. Results Variable – Length of Wire C40 SWG – 32 Diameter/Thickness – 0. 28mm At 2 Volts Length (cm) Volts (V) Amps (A) Resistance.
All these experiments were done at 2V for safety reasons, using a silver wire each time to make the results fair. I believe that I have enough data to make a conclusion; this is because I have chosen a wide range of wires to test on giving me more data. I believe that I made my test accurate by doing tiny things to my work to make it better. For example, I was extremely precise when cutting the wire to its exact measurement, so I was very precise. This would have been an unfair test if I wasn’t accurate and decided to measure free hand. That is just one example of why accuracy is vital when it comes to finding results.
I consider the results very clear, and it is easy to read. It can be interpreted and understood easily, all because the tables are clear and easy to read. I also believe that my experiment with my group was very precise. The variables are suitably and are adequate enough to the investigation, because it is a way of measuring the resistance in a circuit, and I am investigating the affects of material on the resistance levels. Precision was very important, and I think we did great when it came to precision, because we have been accurate, and haven’t made too many errors, if any.
In conclusion, I have clearly outlined the results I obtained from my tests; this has been placed in an easy table. I would like to add, that we have a good range of results, all from are two variables, length of the wire, and the width of the wire. The results are what I expected to be, I will goon to explain what the results show and mean. For now, my work has been displayed in the correct manner, and my accuracy and precision has resulted in to the good results I have achieved. Analysing evidence In this section of my coursework, I am going to have a few graphs. I make the graphs from my results in the table.
I will then explain what the results show, and I will explain how I got the results. My results are listed below. Results Variable – Length of Wire C40 SWG – 32 Diameter/Thickness – 0. 28mm At 2 Volts Length (cm) Volts (V) Amps (A) Resistance (? ) Below are the results for my second variable, this is the thickness or the width of the wire.
Variable – Thickness of a Wire Part No. SWG Diameter or Thickness in mm Volts Amps Resistance C38m The graph clearly shows that one of the wires has produced more resistance than the other. I can conclude that the wire which was thinner, and had a smaller diameter. This says that the bigger the diameter than the less resistance produced, or, the smaller the diameter, the bigger the resistance. This entire conclusion can be observant from the graph.
The statement concludes, the bigger the diameter, the smaller the resistance. For my second graph, I have done the graph with my second variable, which is width against resistance. From the graphs we can automatically see positive correlation.
On this graph, we can see that the bigger the width, the less resistance. So if the width is very small, than there would be more resistance. The statement concludes, the bigger the width, than the less resistance. Conclusion I want to now look back at my prediction and just mention if I am correct with my hypothesis or not. I said earlier that the resistance will be the highest when it is at its lowest width which was SWG 16. I am wrong in saying that, because when I did the experiment, I found that SWG 16 had the least amount of resistance, and it was actually the other way round, so SWG 40 had the highest resistance.
This is probably because there is more area, so resistance is spread over, so I was wrong earlier thinking less area had more resistance, I have learnt from this and now understands why a larger surface area would have a larger resistance. For my other variable I said the highest resistance will come at the longest wire. This hypothesis was correct; I found from all my graphs that 100cm produced the most resistance. This means my explanation of it have a larger area is correct, so this explains that my graphs are accurate and correct. Evaluation
This is the final par of my coursework, this is where I will look back at the work I have done, and see where things could have been differently. I think the way I did my coursework was pretty good, because it was specific to what I wanted. I needed to investigate the resistance levels of certain subjects. I consider that I have done what the criteria has asked for, and are work was through and neat. The work and experiment were relevant to each other, this was good, and because this means that I have done work which does affect what I am looking for.
The procedure I use I think was very suitable, because it was very precise and clear. Finding the resistance levels helped us to analyse the data. We could see which data affected the level of resistance, and others which had no influence at all. The method I used was testing the levels of resistance by setting up a circuit, placing the wire into the crocodile clips and then using the figures from the volt meter and the ammeter, I used Ohms law to convert the numbers in to resistance, so I think this was pretty simple and I was easy to understand.
I think the quality of the evidence is very good, thankfully I can say that I did not make any errors, therefore I can say that there were no times were I needed to identify any anomalies. I did not make many errors at all through my work, so it was a satisfactory experiment. I believe that my experiment was suitable as I said, but there are ways that maybe I could have improved on it.
For example, I believe that if I had repeated my results just one more time, then possibly I would have more data, then I can compare using the same method, but this time I will have more to compare with. I think that my method of analysing and results were reliable, because they justified the system as the results I got, I made substantially longer. I would like to add that I did my coursework very well, and it went well towards my predictions. The positive correlation in the graphs was something I wasn’t expecting, so things like this was good, as it was different.