Resistance coursework - some useful things :: essays research papers

exemption CourseworkPlanningAimInvestigate how the length of a wire affects the current and confrontation of a wire.VariablesThe variables that could change resistance areLength of the wireCross section area (thickness)Changing materialsChanging temperaturesThe variable I am going to change in my experiment is the length of the wire.Prediction and HypothesisI think as you increase the length of the Constantan wire, you too increase the amount of resistance. The current is the flow of electrons the current is dependent on the amount of voltage, which is applied. Voltage is the push given to the current. The current has to go through a rophy, which contains resistance so if you increase that push you also increase the flow of the current. All materials have a slight resistance to electricity factors affecting the resistance are Length, Voltage & Temperature and Surface Area.Preliminary WorkChanging only the length of the wireLengthVoltage (V)Current (A)Resistance (&61527)Short5.4 50.2620.96 hanker5.560.2423.16Longest5.580.1929.36Conclusion the longer the wire, the higher the resistanceChanging only the cross section area of the wireThicknessVoltage (V)Current (A)Resistance (&61527)Single4.731.453.26Double4.441.982.24Triple4.342.072.09Conclusion the thicker the wire, the lower the resistanceChanging MaterialsMaterialVoltage (V)Current (A)Resistance (&61527)Constantan5.510.4811.47Aluminium1.828.630.21Conclusion disparate materials conduct electricity better Changing TemperaturesTemperatureVoltage (V)Current (A)Resistance (&61527)Cold2.276.720.34Hot2.627.000.37Conclusion I came to a conclusion that the decrease in current is the increase in resistance this is because the current although less of it they collide with the resistance causing a decrease in the output voltage. List of equipment and circuit diagramPower pack6 connecting leadsPush switch2 crocodile clipsWire (constantan)VoltmeterAmmeterMeter sticksCircuit diagramAnalysingAs the length increased so di d the resistance.This is because in a longer piece of wire the electrons have to push past more ions.The electrons have a negative charge and the ions have a positive charge. So energy is needed to keep the electrons flowing.