Michael+and+Trevor+Collision+Lab

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


 * Participants**: Michael and Trevor
 * Purpose**: The purpose of this lab is to confirm the law of conservation of momentum.
 * Lab Documents**: [[file:1D Collsions.doc]]

We used a program called Logger Pro. Logger Pro is capable of importing the video of the cars then letting us set the video's scale. Setting the scale of the video's size isn't too imporntant to getting the correct answers. We watched the video frame by frame. while we were doing that, we plotted points on the screen (as seen in image below.) those points then were graphed. Time was on the X-axis, and Location (left and right) was on the Y-axis. We plotted points from before the collision, and after the collision. After all the points were plotted, we analyzed the graph to find velocity of the carts. To do that, we took the slope of the lines on the graph. On the graph it was pretty easy to tell when the collision is (which is where the location lines start to bend.).
 * Brief Description of Experiment**: __Provide a short (one paragraph) description of what was done during this experiment (including the data collection that was done for you and a description of how you collected your data from the video). Supplement this description with images, video, etc. to make clear and interesting. A figure that shows how you collected data off of the graphs or data tables should be included along with rationalle for doing this.__ This lab consisted of taking video of cars colliding on a low friction track, like this one:media type="file" key="Collision 5 small.wmv" width="300" height="300"
 * Data**: Create a table (when appropriate) including all data collected or calculated during the lab. Be sure to include a heading for each column that includes the units of each measurement.[[image:table_1.JPG]]
 * Sample Calculations:** Trevor and I recorded our information in a table, somewhat like this one:
 * || Car 1 || Car 2 ||
 * Mass ||  ||   ||
 * Initial V ||  ||   ||
 * Final V ||  ||   ||
 * Initial M ||  ||   ||
 * Final M ||  ||   ||
 * Both Cars Initial M ||  ||   ||
 * Both Cars Final M ||  ||   ||


 * //Speed calculation//

//grams to Kg

momentum calculation

Percent Difference// || speed = distance / time (slope of the line of fit)

grams/1000 = Kg

P = Mass X Velocity

[(New value - Old value) / Old value] x 100% = Percent Difference || The coefficient of static friction was determined to be 0.45. This was calculated from a measured angle using Newton's first law as desribed in the calculations. 1. Momentum can be positive and negative. In this lab, when the cars were moving right, the momentum was positive. When the Cars moved to the left, the momentum was negitive. After the colision you could tell is the cars had a positive or negative momentum, by looking at which direction they moved in.
 * Results**: Describe the major result of the experiment and how you arrived at this result. Typically, this will refer back to the purpose. For example, if the purpose was to find the coefficient of friction, you would write:
 * Lab Questions**:

2.Percent difference: -Video 1: 4.7% -Video 2: 14.3% -Video 3: 5.924% -Video 4: 19.9% -Video 5: 0% The collision in video 4 had the largest percent change in momentum with 19.9%.

3. If the scale on the video was done incorrectly, it would have no effect on the data's ability to support the law of conservation of momentum. This is true because the measurement of the scale does not matter since we are measuring speed. The distances may not be accurate, but our data should support accurate velocities.

4. The velocity for the cart immediately before the collision would be more accurate to use, when compared to the velocitiy of the same cart just after it was pushed. The velocity immediately before the collision is going to be more accurate because that is the closest velocity you can get right before the collision.

5. 6. An elastic collision is when momentum and energy is conserved, and inelestic collision is when only momentum is conserved.

To be assigned later.
 * Conclusion**: A good conclusion will include:
 * This Lab produced fairly reproducible results. Since you could watch the __exact same__ video every time, it was hard to get different data. The only place for error is if on the video screen you didn't put your dots on the same place of the car for each slide.
 * The results aren't the same because of friction and other outside forces acting on the cars, since this is not a 100% closed system our answers differ a little bit.
 * A suggestion for a simple improvement to the experiment. Think about what caused problems, measurement inaccuracies, or inappropriate simplifying assumptions and propose a change. A sketch may be helpful.
 * 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.//