Any other approved subject area.
Next, I will set the power pack on the lowest voltage possible to ensure that the current passing through the circuit isn't too high which could potentially affect the results because the wire would get too hot. I will place one crocodile clip at 0cm on the wire and the other at 5cm to complete the circuit.
I will then turn the power pack on and record what voltmeter and ammeter readings. I will switch off the power pack, move the crocodile clip that was at 5cm up to 10cm, and switch on the power pack.
Again, I will record the voltmeter and ammeter readings and turn off the power pack. I will repeat this method every 5cm until I get up to cm, taking three readings from both the voltmeter and ammeter each time to ensure accuracy. Apparatus Ensuring Accuracy To ensure accuracy I will record the voltage and the current three times every 5cm and take the average reading.
This will reduce the chance of false readings and will cancel out any anomalous results. I will also ensure that the wire does not heat up too much by confirming that I do not set the voltage too high on the power pack and by maintaining the same the voltage for every reading.
In addition, I will make sure I turn the power pack off after each reading. I will try to make this investigation as accurate as possible. Variables There are different variables that can be changed in this experiment; these are the independent variable.
However, due to my line of enquiry, I will only change the length of the wire. The variables I will control will be the type of wire resistivity and the cross-sectional area of the wire. I will also control, using the power pack, how many volts pass through the wire. Below is a table illustrating the effect of changing the variables see Table 2: Variables Safety I will ensure experimental safety by confirming that all the wires are connected properly and that none of the insulation on the wires is worn.
I will also ensure that there is a clear indication that the power is isolated by means of a switch and an L. I will stand up during the investigation to ensure that I do not injure myself if something breaks.
Results Below is a table of my results Table 3. I have taken three reading and have worked out the average, shown in red.
This confirms the first part of my prediction: In addition, my prediction that doubling the length of the wire increases the resistance by a factor of two is correct see Table 4.Resistance coursework - some useful things Planning: Aim Investigate how the length of a wire affects the current and resistance of a wire.
Variables The variables that could change resistance are:? Physics coursework - resistance of a wire trials in order to decide upon the voltage and lengths of wire to use in the final experiment, the following rough trials were carried out: at 3v: length (cm) voltage (v) current (a) resistance (w) (to 2 d.
The wire will always be constantan (28swg) My prediction is that as the length of the wire increases so will the resistance.
I have decided this because the electrons have to travel further when the wire is longer and more atoms get in the way of electrons travelling and . its length – the longer the wire, the greater its resistance its cross-sectional area A – the greater the area, the less its resistance the resistivity of the material r – the greater the resistivity, the greater its resistance.
Oct 26, · The fact that, as the wire got shorter and therefore the resistance greater, I could not keep the wire from heating up 2.
The wire I was using had a tendency to wind up, diminishing my precision and accuracy in measuring the length. How does Length affect resistance? Coursework Aim To find out how the length of a wire can affect resistance. Factors affecting resistance Temperature.