Stacey,+Jen+&+Sara's+Lab+Report

= ​ 1D Cart Collisions Lab= Date of Publication (Date of Most Recent Edits)


 * Participants**: Stacey Schellong, Jen Grobe, and Sara Binshadler
 * Purpose**:
 * Lab Documents**: [[file:1D Collsions.doc]]


 * Brief Description of Experiment**: In this experiment we chose five videos of car collisions, and we recorded the mass and velocity before and after the collision to find if the law of conservation of momentum applied. With each video we plotted points on the front of both the red and blue cars as they moved from the starting point to the collision point to the point where they stopped moving. We did this so we could find the initial velocity before the collision, as well as the final velocity after the collision. The points we plotted created a graph on the computer, and using this we found the line of best fit. The slope of that line gave us the velocities we needed, and then mathmatically we were able to add the initial velocities of both the blue and red cars and the final velocities of both cars. From this we could determine if momentum was conserved.






 * Data**:

and Total Final Momentum // || For the red cart and blue cart individually we multipled the mass by the velocity. Then we added the two products together to get the initial momentum and final momentum. Example: Video 4.1 Red Cart: 250g x 56.46m/s = 14,240 Blue Cart: 250g x 0m/s = 0 14,240 m/s + 0m/s = 14,240m/s (initial momentum) ||
 * Sample Calculations:**
 * // Total Initial
 * do the same procedure to find final momentum.

This lab was supposed to show that momentum was conserved from before the collision to after the collision. We tested this by calculating the initial and final momentums and finding the percent difference. In our data, the percent difference was extremely high, so we can assume we made a miscalculation or collected incorrect data. Since our data did not show that mass was conserved, we can say we had a poor result.
 * Results**:

**Lab Questions:** 1. We determined that if the cart is moving to the right, the momentum has a positive value, and if it is moving to the left the momentum is negative. This would have an effect on the inelastic collisoins like in Video 4.1 because the momentum before and after the collision are dramatically different. 2. Percent Difference: Video 10.1: 372.96% Video 1.2: 17.99 % Video 4.1: 48.92% 3. ​If we had not correctly scaled the video then the measurements would be incorrect, but the porportions of the measurements would be the same. Meaning that the measurements would be in the wrong unit or no unit at all. 4. It would be better to use the velocity right before the crash. The velocity before the collision would be better to use becasue the measurement at the beginning is changing before the collision. The velocity right before the crash is not changing until the crash. 1. ​The crashes where boths carts were moving towards eachother then collided showed a greater change in kinetic energy. The crashes where one cart was moving and collided into a still cart showed a lesser change in kinetic energy. 2. ​A collision will be inelastic if only one cart is moving and the other is still.
 * Kinetic Energy Lab Questions:**

In this lab our group was unable to collect data that supported the expected result. We believe there were too many components which kept our group from being able to focus on the lab's purpose. We had to focus on all of the technical elements that were necessary in collecting data on five different videos, and in doing so we failed to see that our results were not prooving the conservation of momentum law. There were many aspects of this lab that would have made it more sufficent, these include going over the correct way to collect the data ahead of time (because our group had trouble developing a technique and that likely contributes to our incorrect data), as well as avoiding a completely computer-based lab. If this lab had not involved as many math equations, or if we had been able to create the collisions ourselves instead of analyzing them on the computer, we would have been able to better grasp the law of conservation of momentum.
 * Conclusion**

To be assigned later.
 * Reflection:** (to be completed by each group member individually).

//Don't forget to link to your lab report from the lab reports page and to include a link to your lab report in your reflection.//