Relationship Between The Two Variables and The Trend Formed by The Data

I created a graph above showsing the relationship between the resistance for the conducting wire and the different lengths of a Nichrome wire. My graph is a straight line graph with the majority points lying on the line of best fit. Using the points on the line I applied Ohm’s law and used the formula R = V ÷ I to find the resistance (R) with the voltage (V) and the current (I) that was found before while doing the experiment. I came to the conclusion that, the length of the Nichrome wire increases, the resistance of the conducting wire increases as well. For example, when the length of the wire is 0.2M the resistance is 1.3Ω and then the length of the wire is 0.5m, the resistance is 3.4Ω.

The data trend can be concluded from the experiment is due to, the longer the nichrome wire, the higher resistance will be, assuming that the necessary variables are controlled and method is accurately followed. This is supported by evidence which is presented in the table and the graph, for exmaple, we can see the increase and positive correlation between the length and resitance when the length of wire increases from 0.2 to 0.3 and the resistance from 1.3 to 2.3Ω.A formula can be derived from the graph can be used to further explain the relationship between the two variables and the data trend, which is 6.8*x + 0.1.

In conclusion, I believe the results that I got from my graph further represent and show the relationship between the two variables and the trend formed by the data, the data points were either on or close to the straight line of best fit, and those that did not touch or reach the line were consistent with the trend that followed the graph, and as well showed no anomalous results.

The range of the lengths investigated was sufficient enough to draw a valid conclusion about how changing the length of the nichrome wire would affect the resistance. The gradient line of best fit from my other graph can be found through the formula ‘rise/run’ which gives us an answer of 6.8. The gradient of the formula which can also be calculated by resistance / length to be 6.8. To further investigate the reliability of our results we can use the information and insert it into the formula for resistance which is R = p(L/A), where R stands as resistance, I is the length, A is the cross sectional area and P is the resistivity of the wire. Using the gradient that we calculated, we notice that R / L which equals to 6.8 equals p / A. A is the cross sectional area, can be found to be 0.0000001642m2 using SWG (with a gauge of 26). This shows our resistivity p, would be 0.00000111656Ωm. According to information researched online, the average resitivity of a nichrome wire is between 0.00000110Ωm to 0.00000150Ωm. Comparing the two results for resistivity found, from the experiment and the numbers on line, we can further discuss how reliable our results are. We can see that the resistivity calculated from the experiment falls in between the interval for the average resistivity of a nichrome wire, so we can analyse the results to be reliable and further conclude that few/ to no mistakes were made.

The data trend which can be seen in my graph is in agreement with the predictions made in my hypothesis. They correlated correctly when I states that “I predict that the longer the wire, the larger the resistance will be due to the voltage being higher in a longer wire and the current remaining the same. “ My graph for the experiments shows the consistency the predicted graph in the hyptheiss which shows the positive correlation. Validity of methodI think the method was valid to the experiment being done, it contained some minor errors which have affected the results we got. I believe the most effective one towards our results was the lack of equipment specializing for that experiment. This is due to results and existing experiment, however I believe my method would have been further improved to control the variables better like perhaps the temperature to make sure results were most accurate and consistent. I used the same piece of wire throughout the experiment which meant that duering it being hooked up to the circuit for extensive periods of time the temperature on it may have increased therefore affecting the results. We can see that a lack of controlling the variable of temperature had not directly affected the reliability of the results as they were still in range of the set range for nichrome wire on the internet. As can be seen there is still sufficient evidence to come to the conclusion we did.

As mentioned previously, the variable of wire temperature could have improved and controlled more accurately. This could be done using special equipment for experiment, however a better approach might be to use a new piece of wire each time for every new trial, however this could bring other faults to the accuracy of results affected by the wire, as well as being time consuming. In addition, the time in between each variable would have been measure, the changes in length between each length was 0.1 if that were to be increased we could have a much more longer range of data which would therefore bring upon more results, perhaps by measuring in increments of 0.5 , giving us a 0.5, 0.10m, 0.15m, 0.20m, 0.25m and s one. Increasing the range of values and thereby ending with more lengths up to 1m.ExtensionTo extend this investigation, I could carry out the same experiment with different types of wire like other groups used to test different materials and see how those results correlate with the ones I had from nichrome.