# Investigation Essay

390 WordsAug 11, 20152 Pages
Investigation of the free falling of a paper tape Data collection serial number | distance,d±0.1cm | | 1 | 1.3 | | 2 | 1.5 | | 3 | 1.7 | | 4 | 2 | | 5 | 2.3 | | 6 | 2.5 | | 7 | 2.8 | | 8 | 3 | | 9 | 3.3 | | Data presentation Conclusion and evaluation Conclusion : According the above graph, We can find that the distance and serial number have the liner relationship. We can use the formula: gmax=0.275cm(0.02s)2×0.01mcm=6.875m/s2 gmin=0.225cm(0.02s)2×0.01mcm=5.625m/s2 gbestfit=0.253cm(0.02s)2×0.01mcm=6.325m/s2 ∆g=gmax-gmin2=0.025 ∆ggbestfit×100%=9%. Because 9% smaller than the 10%, So we prove that the lines near than a straight line. But the error we don’t have the way to cut out. If we compare the g reference value, gbestfit-gtheorygtheory×100%=30% range=gbestfit±∆g=6.30,6.35 Evaluation When I finish my experiment and calculate the value of error. My systemic error not very big but also exist in the experiment, it’s 9%. Maybe when we do the experiment, the friction between the paper tape and ticker timer exist.when the paper tape attach the ticker timer , it will have the normal force between them. μN .For the random error, it’s very big for my experiment , not accuracy. And we read number maybe not very accuracy because the minimum division is not precise for mm or more precise measurement. We use the cm to fill the blank for the data. Improvement Although we can’t cut out the error , Buy we can try to decrease the error. For the systemic error, we can use the soluable oil to make the friction. We also can change other source to instead of the hard paper to add probability of the experiment. For the random error we can measure many times for the distance and get the average value to sure the final result of distance. Then I think we can make the g close to the reference number 9.81/m2.For example ,we can