Resistivity Coursework
Introduction - define the physical quantity resistivity in words and showing that you understand what it means
Aim - stating clearly what you are trying to do
Theory - Use the formula for resistivity to rearrange and compare with the equation for a straight line, sketch the graph you will draw labeling the axes and what shape of graph you expect to get. Identify all the symbols and exactly what they mean. State what you are going to change and what you will measure. Show what calculations you will do.
Circuit Diagram - draw a circuit diagram of that could be used to get the results you have been given.
Analysis - complete the table for R. Calculate the area in the correct units. Draw a table of what you are going to plot.
Graph - this is the important part. Choose scale carefully to give you the biggest graph possible. Label axes including units, plot points accurately, draw a line of best fit, measure the gradient. Use the gradient to calculate the resistivity of the unknown metal.
Conclusion - use the table of known resistivities to state which one you think your unknown metal is.
The results in the table below are for a wire of unknown material and diameter 0.45 mm
| l/m |
V/V |
I/A |
R/Ω |
|
2.5
|
9.8
|
0.600
|
|
| 2.2 |
9.7
|
0.674
|
|
|
1.9
|
9.9
|
0.796
|
|
|
1.6
|
9.7
|
0.927
|
|
|
1.3
|
9.8
|
1.153
|
|
|
1.0
|
9.6
|
1.146
|
|
|
0.7
|
9.8
|
2.141
|
|
|
0.4
|
9.9
|
3.867
|
|
|
Material
|
Resistivity ρ / x 10-8Ωm
|
|
Aluminium
|
2.65
|
|
Brass
|
8
|
|
Copper
|
1.7
|
|
Constantin
|
47
|
|
Manganin
|
45
|
|
Silver
|
1.6
|
|
Steel
|
15
|
|
Nichrome
|
104
|