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Introduction

Investigation - To find how the resistance of a wire varies with length 1st Section - Prediction and Planning Introduction: I am going to conduct an experiment to investigate how the electrical resistance of a wire changes in relationship with it's length. Prediction and Planning: I think and have good reason to believe that as the length of the wire increases, the resistance will increase too. Not only that but I also believe that the rate at which the resistance of the wire increases will be directly proportional to it's length. ...read more.

Middle

When there is potential difference across a conductive material all the free electrons arrange themselves in lines going in the same direction (this is electric current). Resistance occurs when charged particles in the current collide with fixed particles in the material. So as you increase the resistance of a material you also need to increase the force used to push the current. Resistance (ohm's/?) = Volts divided by Current (Amperes) This is Ohm's Law, However it only applies if the temperature of the wire stays constant. ...read more.

Conclusion

Then we repeated the process twice to allow us to take an average. We started at 500mm because an earlier experiment has shown that if the wire is too short then the wire will get hot and the readings of the Voltage and Current will fluctuate wildly. The material and cross-sectional area of the wire was kept constant for the whole experiment. 2nd section - Obtaining evidence Length (mm) Voltage (v) Current (amps) Resistance (?) 500mm 3.18 0.79 4.03 600mm 3.33 0.64 5.20 700mm 3.40 0.56 6.07 800mm 3.47 0.51 6.80 900mm 3.43 0.45 7.62 1000mm 3.51 0.42 8.36 1100mm 3.54 0.38 9.32 1200mm 3.58 0.34 10.53 1 ...read more.

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