For this piece of coursework I have been asked to investigate into the resistance of wires when the length is changed.
The objective for my coursework (as already stated above) is to investigate how changing the length of wire can affect the resistance.
There are factors which can affect how accurate our expriment is come on four levels.
As in any scientific experiment, there are always variables ( "likely to change or vary subject to variation; changeable." ) which can alter a potentially good set of results into a bad set full of anomalies. In this particular test there are five main variables.
Length affects resistant, this is the variable which we are changing. As water in a hose pipe, the longer the pipe the longer the water takes to reach its destination. This can be applied in the variables of resistance. The electrons 'bounce' off the atoms - this causes the electrons to head elsewhere rather than the desired direction.
In a long tube there are more atoms, this slows the electrons down as they 'bounce' off into another direction. In a short tube, there are less atoms which means there are less to deflect the electron any more speeding the speed up. In theory, the length should be proportional to the resistance. This is the variable which we will be changing in the experiment.
Diameter, we are keeping the same. Again, with the hose pipe, if the tube is thick it allows more water molecules to pass through at one time compared to a thinner tube. Once again this can be applied to resistance in wires.
If the wire is 'thin' then there are less paths for a electron to travel. This slows down the electron slowing down the speed. If the wire is thick...