GCSE Physics SC 1 An experiment to investigate how the electrical resistance of a wire changes in relationship to its length- preliminary Prediction: I think that as the length of the wire increases so will the electrical resistance. Also I predict that my graph may have a strong positive correlation. I will also try to incorporate the equation y = m x + c. This will help me to find out the gradient of the graph. I predict that my graph my look something like this: Apparatus: power pack Ammeter Voltmeter Wires Metre rule with nichrome wire in following thickness’: 1. 0.

### 315 mm 2. 0. 375 mm 3. 0. 457 mm 4.

0. 559 mm Crocodile clips Preliminary Method: I set up the experiment as follows: Aim ” ee Fitzpatrick 10 a I set my ammeter up in series and my voltmeter up in parallel. Then I then turned on the power pack, after my teacher checked my experiment to make sure it was safe, and changed that dial so that the voltmeter was at 2 volts. This was kept constant throughout the experiment. The only thing that I changed was the length of nichrome. I tried to keep the temperature constant by finishing all the experiment on one day because otherwise the particles may move quicker if the temperature is increased.

### The Essay on The Subject Matter of Experiments

A well-designed experiment tells us that changes in the explanatory variable cause changes in the response variable. More exactly, it tells us that this happened for specific subjects in the specific environment of this specific experiment. No doubt we had grander things in mind. We want to proclaim that our new method of teaching math does better for high school students in general or that our ...

I then recorded the results of the amps in a table. (See below) I recorded the results of the highest and lowest measurement of each thickness of wire and I chose the wire that had the greatest range. Thickness of wire (mm) Voltage Current (amps) 20 cm Current (amps) 1 m Range of amps 0. 315 2 0. 73 0. 14 0.

59 0. 375 2 0. 95 0. 17 0. 78 0.

457 2 0. 98 0. 31 0. 67 0. 559 2 0.

89 0. 44 0. 45 Instead of choosing the wire with the largest range I am deciding to use all of them because they all have quite a large range and also they have an irregular pattern. I think that I could improve this experiment by doing each measurement 3 times and taking an average. I will do this in my next experiment. An experiment to investigate how the electrical resistance of a wire changes in relationship to its length Plan: Set up the experiment as shown in the diagram before.

Adjust dial until the voltmeter reads 2 volts. Record current on ammeter Repeat the experiment with all four lengths of wire I will take recordings at the following measurements: 20 cm 40 cm 60 cm 80 cm 100 cm/1 m I won’t go any lower than 20 cm because sometimes this can cause the overheating of the nichrome. I will need to use the following equation to find out the resistance of the wire against length: RESISTANCE = VOLTS AMPS R = V I Safety: Tie back hair- to ensure your hair does not cover your face and get in the way of the accurate readings and the experiment Get the teacher to check your plan and that your experiment is safe and not set-up backwards therefore resulting in a small explosion. Do not turn the power pack up high because the voltmeter and ammeter can only handle so much current going through them! Method: I am going to set up my experiment like the diagram above and then record the results in the table below.

I am going to try and keep all the possible factors the same except for the length of the wire. Wire length Voltage Amps Average amps Resistance R = V/I 20 cm 2 1 = 0. 72 2 = 0. 74 3 = 0. 71 0.

72 2. 80 40 cm 2 1 = 0. 38 2 = 0. 40 3 = 0. 40 0. 39 5.

13 60 cm 2 1 = 0. 28 2 = 0. 27 3 = 0. 27 0. 27 7. 40 80 cm 2 1 = 0.

### The Term Paper on Length Of The Wire Resistance Current Results

... relation ship between length of the wire and resistance. Conclusion The results I have gained from my experiment agrees with my ... 0. 4 amps again I will take the voltmeter readings for the 10 different lengths of wire. Then I ... electrons through a circuit current is measured in amps. A circuit can only possess a current if ... to adjust the ammeter reading to 0. 2 amps. Then I will place my crocodile clips ...

18 2 = 0. 18 3 = 0. 19 0. 18 11. 11 100 cm 2 1 = 0. 15 2 = 0.

14 3 = 0. 15 0. 15 13. 30 This table shows the results of resistance of the diameter of wire 0. 315 mm.

Wire length Voltage Amps Average amps Resistance R = V/I 20 cm 2 1 = 0. 98 2 = 0. 96 3 = 0. 95 0. 96 2.

08 40 cm 2 1 = 0. 49 2 = 0. 49 3 = 0. 50 0.

49 4. 08 60 cm 2 1 = 0. 31 2 = 0. 32 3 = 0.

32 0. 32 6. 25 80 cm 2 1 = 0. 21 2 = 0. 22 3 = 0. 23 0.

22 9. 09 100 cm 2 1 = 0. 18 2 = 0. 17 3 = 0.

18 0. 18 11. 11 This table shows the results of resistance of the diameter of wire 0. 375 mm Wire length Voltage Amps Average amps Resistance R = V/I 20 cm 2 1 = 0. 99 2 = 0.

97 3 = 0. 97 0. 97 2. 06 40 cm 2 1 = 0. 62 2 = 0. 62 3 = 0.

61 0. 62 3. 22 60 cm 2 1 = 0. 46 2 = 0.

48 3 = 0. 47 0. 47 4. 25 80 cm 2 1 = 0. 40 2 = 0. 39 3 = 0.

38 0. 39 5. 12 100 cm 2 1 = 0. 31 2 = 0. 32 3 = 0. 32 0.

32 6. 25 This table shows the results of the resistance of the diameter of wire 0. 457 mm Wire length Voltage Amps Average amps Resistance R = V/I 20 cm 2 1 = 0. 90 2 = 0. 89 3 = 0. 90 0.

90 2. 22 40 cm 2 1 = 0. 83 2 = 0. 84 3 = 0. 84 0.

84 2. 38 60 cm 2 1 = 0. 64 2 = 0. 62 3 = 0.

63 0. 63 3. 17 80 cm 2 1 = 0. 51 2 = 0. 52 3 = 0.

51 0. 51 3. 92 100 cm 2 1 = 0. 46 2 = 0. 44 3 = 0. 45 0.

45 4. 44 This table shows the results of the resistance of the diameter of wire 0. 559 mm I will now draw a graph of resistance against length for each graph. I will then try to incorporate the equation y = m x + c. (See attached graph sheets) Conclusion: I think that from my results I can safely say that my prediction was right. The resistance did change in proportion to the length.

This is because as the length of the wire increased the electrons that made up the current, had to travel through more of the fixed particles in the wire causing more collisions and therefore a higher resistance. Evaluation: physics gcse project.