Betlejewski 1 Hailey Betlejewski Partners: Elizabeth B., Jean S., Nicki K. 9 October 2013 PHYS 1051L, Sec 35 The Effect the Spring Constant, Stretch Distances and Mass Have on the Period of Oscillation Abstract The question investigated in this experiment was, what affects the period of oscillation of a spring/mass system? Based on this question, our hypothesis is that the period of oscillation is impacted only by the mass. In order to address this question, an experiment was done testing to see if the spring constant, the mass used and the stretch distance impacted the period of oscillation. The spring constant was found by using 5 different springs with the same mass and finding the slope of each. Each variable was tested separately to see if they solely impacted the period. Each test used the same system to measure the period and each had the same dependent variable. The dependent variable was always the period of oscillation. The independent variable varied based on what was tested; either the mass, stretch distance or spring type. Each had their own control variables to that fit with its specific experiment. Data from our experiment was compared to two other groups. The results showed that the mass used and the spring constants were the variables that had an impact on the period of oscillation. As the mass increases, the period of oscillation increases. Also as the spring constant decreases, the period of oscillation increases. This is supported with the data from the two other groups as well as our own results. Based on our results, our hypothesis is supported but needs to be revised because it is not the only variable impacting the period. The new hypothesis would be the period of oscillation is impacted by the spring constant and the mass. Experimental Design Effect of Mass Hypothesis: Independent Variable: Dependent Variable: Control Variables: Effect of Stretch Distance Hypothesis: Independent Variable: Dependent Variable: Control Variables: The period of oscillation is impacted by the mass used. Mass used. Period of oscillation. Spring/mass system used, spring used (C1), stretch distance (40cm) The period of oscillation is impacted by stretch distance used. Stretch distance. Period of oscillation. Spring/mass system used, spring used (C1), mass used (250g) Betlejewski 2 Effect of Spring Constant Hypothesis: The period of oscillation is impacted the spring used Spring used. Period of oscillation. Spring/mass system used, stretch distance (5cm), mass used (250g) Independent Variable: Dependent Variable: Control Variables: Results Table 1. This group of tables represents the data collected from our group. They are set up this way in a group to show side by side which variables impacted the period of oscillation and which ones didn’t. Each variable was tested: mass, spring constant, and stretch distance. Stretch distance had no impact on the period but the other two variables did. As the mass increases, the period increases. As the spring constant increases, the period decreases. The stretch distance stayed constant. The uncertainties for each period are also shown. (a) Mass(g) 150 200 250 300 350 (b) Spring Constant (cm) 19.4 ± .77 33.7 ± .20 51.6 ± .23 55.8 ± .55 77.7 ± .25 Period of Oscillation .634 ± .0017 .748 ± .0068 .810 ± .0037 .890 ± .0033 .949 ± .0094 Period of Oscillation .812 ± .0049 .548 ± .0025 .431 ± 7.6e-4 .425 ± 4.6e-4 .352 ± 9.5e-4 (c) Stretch Distance (cm) 5 10 15 20 25 Mass vs. Period 1.2 Period (seconds) 1 y = 0.061x0.4694 R² = 0.9943 0.8 0.6 Series1 0.4 Power (Series1) 0.2 0 0 100 200 Mass (grams) 300 400 Period of Oscillation .812 ± .0049 .817 ± .0014 .815 ± .0016 .859 ± .0042 .874 ± .016 Betlejewski 3 Figure 1. This graph shows the mass vs. the period of oscillation. As you can see, as the mass increases, the period of oscillation also increases at a constant rate. This data is strictly from our group and reflects the results in Table 1(a). Period (secojnds) Spring Constant Vs. Period 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 y = 4.6766x-0.599 R² = 0.9926 Series1 Power (Series1) 0 20 40 60 80 100 Spring Constant (N/m) Figure 2. This graph shows the spring constant vs. the period of oscillation. As you can see, the period decreases as the spring constant increases. This data is strictly from our group and reflects the results in Table 1(b). Period (secojnds) Stretch Distance vs. Period 0.9 0.89 0.88 0.87 0.86 0.85 0.84 0.83 0.82 0.81 0.8 0.79 y = 0.7459x0.0439 R² = 0.6597 Series1 Power (Series1) 0 10 20 30 Stretch Distance (cm) Figure 3. This graph shows the stretch distance vs. the period of oscillation. As you can see, there really is no pattern being shown. While there are two higher periods, this can be from error. This data is strictly from our group and reflects the results in Table 1(c). Betlejewski 4 Table 2. This group of tables represents the data collected from Group 5. They are set up this way in a group to show side by side which variables impacted the period of oscillation and which ones didn’t. Each variable was tested: mass, spring constant, and stretch distance. Stretch distance had no impact on the period but the other two variables did. As the mass increases, the period increases. As the spring constant increases, the period decreases. The stretch distance stayed constant. The uncertainties for each period are also shown. (a) (b) (c) Mass(g) Period of Spring Period of Stretch Period of Oscillation Constant Oscillation Distance Oscillation (cm) (cm) 100 .380 ± .0034 4 .347 ± .0042 5.3 ± .0096 1.10 ± .004 150 .479 ± .0076 5 .351 ± .0041 7.8 ± .013 .985 ± .0098 200 .509 ± .0054 6 .354 ± .0011 33.7 ± .35 .453 ± .003 250 .551 ± .0053 7 .348 ± .0006 49.4 ± .62 .38 ± .0022 300 .607 ± .0072 85.6 ± 1.4 .146 ± .0082 8 .348 ± .0024 Table 3. This group of tables represents the data collected from Group 6. They are set up this way in a group to show side by side which variables impacted the period of oscillation and which ones didn’t. Each variable was tested: mass, spring constant, and stretch distance. Stretch distance had no impact on the period but the other two variables did. As the mass increases, the period increases. As the spring constant increases, the period decreases. The stretch distance stayed constant. The uncertainties for each period are also shown. (a) Mass(g) 150 200 250 300 350 (b) Period of Oscillation .285 ± 1.4e-4 .329 ± 1.6e-4 .365 ± 1.6e-4 .399 ± 1.2e-4 .430 ± 2.3e-4 Spring Constant (cm) 7.78 29.3 50.7 55.3 70.4 (c) Period of Oscillation 1.12 ± 5.5e-4 .54 ± 2.6e-4 .46 ± 9.3e-3 .43 ± 2.6e-4 .36 ± 1.1e-4 Stretch Distance (cm) 2 4 5 6 7 Period of Oscillation .37 ± 1.8e-4 .37 ± 7.3e-4 .37 ± .0051 .37 ± .0011 .37 ± .0011 Conclusion and Discussion Our hypothesis states that the period of oscillation is impacted by the mass used. After completing this experiment, we can support our hypothesis. However, our hypothesis can be supported but it must be revised because the mass wasn’t the only variable that impacted the period of oscillation. The new hypothesis would be the period of oscillation is impacted by the mass used and the spring constant. We were to find what impacts the period of oscillation of a spring/mass system. The variables that had an impact on the period of oscillation were the mass used and the spring constant. We have found based on our own groups’ results that as the mass increases, the period also increases. This is shown clearly in Table 1(a).You can see in this table Betlejewski 5 that the period is increasing as the mass increases. This is also supported by the Group 5 and Group 6 data shown in Table 2(a) and Table 3(a)—they show the same patterns as our data. Visually you can see the linear pattern in Figure 1. Not only did we discover this but we can conclude that as the spring constant increases, the period of oscillation decreases. This evidence is clearly shown in Table 1(b). You can see clearly that when the spring constant increases, the period of oscillation decreases. This is also supported by Group 5 and 6. They show the same results which can be seen in Table 2(b) and Table 3(b). Table 1(c) also shows that the stretch distance does not impact the period of oscillation because the periods stay constant as the stretch distance differs. Group 5’s data (Table 2(c)) and Group 6’s data (Table 3(c)) supports this claim because they too have a constant period when different stretch distances were used. This is visually shown in Figure 3. There is no pattern that shows in the graph and the first three points are rather constant. These results show that the mass impacts the period of oscillation. This makes logical sense that the period would increase as the mass increases because the more weight there is, the more stretched out the spring will become causing a larger period. It also makes logical sense that the spring constant would impact the period of oscillation. It makes logical sense because each spring constant represents a different type of spring. Each spring stretches in its own way—some stretch more than others and so on. If they are different springs they are bound to stretch differently causing a difference in the period of oscillation. It also makes logical sense that the stretch distance would have no impact on the period of oscillation. This is because it shows where the equilibrium is but would not impact the period. The experiment was run electronically through data studio which leaves little room for human error since all the data was recorded on a computer. Human error could be incorrect measurements of the masses used or incorrect measurements of the spring constants. There are some data that falls outside of the identified pattern in our data in Table 1(c). The last two periods seem higher than the rest and don’t really fit. Random errors like this can be caused by incorrectly measuring the periods on the computers part. Not every measurement can be perfect, not even if it is done electronically. These random errors can be decreased by running more trials in order to minimize error by averaging over a larger number of periods obtained. Without the presence of random error incorrectly measuring the period of oscillation for the last two measurements in the stretch distance vs. time would be closer to the first three measurements. A systemic error that could have happened would be the added weight of the paper card on the spring/mass system that was used. The paper was never weighed and that could have influenced results by having a heavier mass than intended. This could easily be avoided by taking if off and weighing it. A constraint I noticed in this experiment was that some of the springs were hard to stretch making it hard to measure at the same stretch distance. Aside from any errors that may occur, the results showed that as the mass used on the system increases, the period of oscillation also increases. It also showed that as the spring constant increases, the period of oscillation decreases. Based on our own results and the results of Group 5 and 6 our original hypothesis is supported but can be revised because the mass wasn’t the only variable to impact the period of Betlejewski 6 oscillation. The new revised hypothesis would be, the period of oscillation is impacted by the spring constant and the mass used. References The data referenced in this experiment was shared in class during lab 8. It is the results from Group 5 and Group 6.