Lab Report PhyI-04: Energy and Linear Momentum Conservation in Elastic and Inelastic Collisions PDF

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Lab Report PhyI-04: Energy and Linear Momentum Conservation in Elastic and Inelastic Collisions...

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Physics I Laboratory

Faculty of Science, Ontario Tech University

Lab Report PhyI-04: Energy and Linear Momentum Conservation in Elastic and Inelastic Collisions Student’s name: _______CRN: 411 Date: Nov 17th, 2021 Weight = 250g 1= blue cart , 2= red cart (red cart stayed at rest) Initial and Final Velocities, Coefficient of Restitution Table 1 Run #

m1, kg

m2, kg

t1, s

v 1 , m/s

v 2, m/s

t2, s

, m/s

, m/s

e

1

0.251

0.234

0.64

0.399

0.000

0.80

0.000

0.340

0.852

2

0.251

0.484

0.92

0.451

0.000

1.10

-0.139

0.288

0.947

3

0.251

0.234

1.39

0.406

0.000

1.44

0.094

0.330

0.581

4

0.251

0.484

1.28

0.556

0.000

1.31

0.132

0.319

0.336

5

0.251

0.234

2.14

0.330

0.000

2.16

0.073

0.222

0.452

6

0.251

0.484

1.35

0.371

0.000

1.38

0.035

0.173

0.372

Momentum and Kinetic Energy Table 2 Run #

P, kg·m/s

P', kg·m/s

% difference

K, kg·m2/s2

K', kg·m2/s2

Loss of Kinetic Energy, %

1

0.1002

0.0761

24.05

0.0200

0.0136

32.0

2

0.1133

0.1029

9.18

0.0248

0.0220

11.3

3

0.1052

0.1007

4.28

0.0222

0.0138

37.8

4

0.1403

0.1358

3.21

0.0392

0.0247

37.0

5

0.0811

0.0703

13.3

0.0137

0.0060

56.2

6

0.0933

0.0843

9.64

0.0173

0.0073

57.8

Collision time __________0.05 s_________

Conclusion: Lab Report PhyI-04: Energy and Linear Momentum Conservation in Elastic and Inelastic Collisions

Physics I Laboratory

Faculty of Science, Ontario Tech University

The purpose for this experiment was to demonstrate two fundamental physics laws, linear momentum, and energy conservation with elastic and inelastic collisions in one dimension. The results were analyzed graphically and numerically to prove these laws of conservation. The lab method used was two collision carts with magnets or velcro Lab Report PhyI-04: Energy and Linear Momentum Conservation in Elastic and Inelastic Collisions

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Physics I Laboratory

Faculty of Science, Ontario Tech University

depending on the run of the experiment and added mass. The carts will be placed on a track and cart 2 will be pushed towards cart 1, from there their velocities With elastic and inelastic collisions in one dimension, the goal of this experiment was to show two fundamental physics laws: linear momentum and energy conservation. To prove these conservation laws, the data was evaluated graphically and mathematically. Two collision carts with magnets or Velcro, depending on the run of the experiment, and an increased mass were used in the lab. Cart 1 will be pushed towards cart 2 on a track, and their velocities will be monitored with a rotational motion sensor right before and after the impact. Also, just before and after the collision, the linear momenta and total kinetic energy will be measured. Three different scenarios will be considered: perfectly elastic, perfectly inelastic, and slightly inelastic, with two runs for each with a variable mass. The restitution coefficient can also be estimated using the gathered data, and the collision time for the completely elastic collision will be measured. The cars would be able to cling together and maintain some speed because of this. For each experiment, two runs were performed for two reasons: the first was to ensure that the expected outcome occurred more than once, ensuring that the experiment was working, and the second was to further prove the physics laws with varying masses, as mass should not affect the overall outcome and the velocities should compensate for the addition/subtraction of mass. There were some notable discrepancies when comparing the graphs from each of the three studies. For each experiment, total momentum was conserved, meaning the overall momentum of the two carts before and after the collision was the same. This is true for all isolated systems according to Newton's third law of motion. The % changes between the momentum before and after the collision are plausible. If the track was not level, a few sources or errors could account for the discrepancy, because a totally horizontal level track will produce the best outcomes. However, keep in mind that during the perfectly inelastic collision, the carts were not attached together like two balls of clay would be, thus they weren't really stuck together, merely velcroid together. Hence, for this collision test, it might Lab Report PhyI-04: Energy and Linear Momentum Conservation in Elastic and Inelastic Collisions

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Physics I Laboratory

Faculty of Science, Ontario Tech University

be best to use magnets that attract. It's also possible that not taking exact figures from when the collision began and finished will have an impact on the experiments. Because it was difficult to pinpoint the specific location, the % difference may have been influenced. Only in the perfectly elastic collision was the kinetic energy conserved in all the experiments. This is due to the fact that the kinetic energy involved in the elastic collision is turned into potential energy as the carts approach each other and then back into kinetic energy as they bounce off each other. Because of the loss of kinetic energy due to the collision and the fact that the carts cling together, kinetic energy is not conserved in partially/perfectly elastic collisions, which might change into heat or internal energy. This, together with the fact that total momentum is preserved, rules out the possibility of kinetic energy conservation. Only the fully elastic collision was studied, and the collision duration was calculated by dividing the width of the derivative of the velocity function by half of the maximum. The collision time was 0.05 seconds. This result is far lower than the average collision time utilised in the experiment to calculate velocities. However, because there were not many points to choose from on the collision time graph, this value is only an estimate. Overall, the value is appropriate because finding the exact start and end of the collision on the other graphs was difficult. Lastly, this lab made me make real-life connections to the Conservation of Momentum and Kinetic Energy explained in Newtons 3rd Law

Lab Report PhyI-04: Energy and Linear Momentum Conservation in Elastic and Inelastic Collisions

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