Recording and presenting your data
1 Calculate the cross-sectional area A of the wire using the equation
A = ¼πd2
2 Record your values for m and x in a table of results. Include columns for F and for the stress and the strain, where
F = mg
Stress = F/A
Strain = x / L
Where F is the applied force, x is the extension, A is the cross-sectional area and L is the original length and g = 9.81 m.s-2.
3 Plot a graph of stress (y-axis) against strain (x-axis).
Analyzing your data
1 Calculate the gradient of your graph.
2 The Young modulus E of the material of the wire is given by the equation
E = stress / strain. Use your answer to 1 to determine the Young modulus of the material of the wire.
Evaluation
The procedure you carried out including what steps were taken to reduce error.
1 Estimate the actual error in each measurement taken.
2 Describe any limitations or problems with the method used to determine the Young modulus.
3 Suggest why a large value of L was used in this experiment.
4 Suggest two ways in which the accuracy of the measurements taken could be improved.
5 Look up the ‘true’ value for the Young modulus of the material of your wire. Comment on the difference between this ‘true’ value and the value you obtained from your experiment.
Key learning objectives
• To experimentally determine a value of the Young modulus of a material.
• To illustrate the importance of making some variables large in order to reduce errors in small readings.
Expected Results

material of wire | Young modulus / N m-2 | Copper | 1.3 × 1011 | Constantan (copper-nickel alloy usually consisting of 55% copper and 45% nickel) | 1.6 × 1011 | Aluminum | 7.1 × 1010 |

Report Preparation and Writing
Report will based on three major parts
Introduction
Each student in group will write and submit this part individually. It should not be more than one page (A4). The contents of this part should be as followed. * Objectives of the experiment. * Your understanding about this experiment and Young’s Modulus. * Brief description of procedure followed during experimentation.
Results
Each group will prepare and submit only one set of this part. It will include all the measured data, calculations, tables and graphs.
Discussion
Each student in group will write and submit this part individually. It should not be more than one page (A4). The contents of this part should be as followed. * Analysis of results and experiment, in itself. * Description regarding limitation in experimental procedure and instruments and proposed improvements. * Conclusive remarks about the experimental findings.