Young Modulus of Copper Essays

Young Modulus of Copper Essays Young Modulus of Copper Paper Young Modulus of Copper Paper From the above results , we can see that there is a 12. 1 % random error in finding the Young modulus of copper . One of the reasons for such errors is the non-uniformity in cross sectional area . When a wire is stretched by a force , the length of course will increase , but at the same time the cross sectional area of the wire will also vary . This little variation will affect the calculation of Young modulus by a pretty substantial degree . Besides , there could have been parallax error which occurs when the eye is not placed directly opposite a scale which a reading is being taken . Moreover , reading errors is another error when guess work is involved in taking a reading from a scale when the reading lies between the lines. Concerning the large systematic error , the main reason for it is the impreciseness of equipments . Since the extension is so small (about 0. 01mm), using a meter rule(minimum scale is only 1mm) to measure it is absolutely unacceptable as many minor data will be omitted . In addition , the length of wire in part 1 and part 2 is different , this will end up in not being a fair test . As the elastic limit depends little on the length of the wire , the wire in part 2 may undergo plastic deformation earlier that we may have ignored . Conclusions : Comparing the shape of the graphs , it is obviously that the result is close to the theory . Although the random error is almost 12% , it is still acceptable as human errors must exist inevitably. However , the systematic error in this experiment is quite large due to the inaccuracy of equipments , therefore better design or improvements are required . Possible Improvements : 1. Repeat the experiment for several times to get a more precise average reading . 2. Use a longer copper wire to lower the percentage error in measurement . 3. A thinner copper wire is also recommended as it can make the extension larger for better resolution . 4. Use a large Vernier Caliper instead of meter rule so that the extension of the wire can be measured more accurately . If it is possible , it is also suggested to use a electronic Vernier Caliper as well . 5. Add weights at smaller intervals instead of 50g jumps . This would help in making the graphs more accurate, therefore allowing us to read off the graph more accurately and getting better readings.