The paper tells that different materials have different mechanical properties that make them fit for various uses. Aluminum, Low Carbon Steel and High Carbon Steel have different strengths and they break at different loads. The Young’s Modulus (E) is a measure of stiffness of an elastic material defined as the ration of stress to the corresponding strain when a material is put under tension or compression. The most commonly used test specimens are cylindrical in shape. For this experiment, however, a wire was used as a specimen. When more loads are applied the specimen breaks at the centre. The data of load versus extension of the specimen is collected and used in calculation of stress and strain. The values are plotted on an X-Y graph and yield a typical graph. From the graph several material properties could be calculated and observe. The following experiment investigates the Young’s Modulus of a piece of wire subjected to tension. To get the Young’s Modulus, stress and strain of the wire must be calculated from the recorded results. The linear section of the graph is referred to as the yield strength where the material shows elastic behavior and it is used in the calculation of E. On the other hand, the other part of the graph is referred to as the non linear section. The yield point is the transition between the linear and the non-linear sections, and the magnitude of stress at this section is termed as the yield strength (σY). The slope of the linear section of the curve gives the material’s Young’s modulus, given in GPa. The formula for calculating young’s modulus is shown below. ...

e yield point is the transition between the linear and the non-linear sections, and the magnitude of stress at this section is termed as the yield strength (?Y). The slope of the linear section of the curve gives the material’s Young’s modulus, given in GPa. The formula for calculating young’s modulus is shown below. ..................................... 4 .............................. 5 Figure 2: A typical stress v strain plot from a tensile test Objectives The objective of this experiment is to determine the Young’s Modulus when a piece of wire is subjected to varying forces. Apparatus The following apparatus were used during the experiment: 1 x G-clamp, approximately 10 cm jaw 1 x 2 wooden blocks 1 x single pulley placed on a bench clamp 1 x meter rule 1 x Adhesive tape 2 x cardboard bridges 1 x mass hanger with 8 slotted masses, 100g each 2 x lengths of copper wire 1 x safety spectacles Wire rolls and threads Procedure The experiment set up was as shown in figure 3 below. Figure 3: Experimental setup 1. After the set up was made, a copper wire was stretched and fixed horizontally along the bench as shown in figure 3 above 2. A maker was made from the adhesive tape and it was attached to the wire to make it less 2 m from the clamp and approximately 5 cm from the pulley. The marker was set to line up with the meter rule so that it could be used to measure the extension of the wire. A loop was made in the end of the wire for loading 3. The original length of the wire was measured and recorded. This was the length from the clamp to the marker. A small mass of 100g was then placed to stretch the wire and the length recorded. 4. The masses were increased gradually in steps of 200g while the force and the corresponding extension was recorded in each case. The
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