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=media type="youtube" key="4SiGy3fepaw" width="425" height="350"media type="youtube" key="WNbUT0NKu6Q" height="344" width="425"= =Pre-Lab: We will be using two cars and a ramp to set up an elastic collision. A heavier will go down a ramp and hit a stationary lighter weight car. We will find velocities through bomber problems in order to be the most accurate.= = = =Equipment--2 matchbox cars (different sizes)= =yard stick= =carbon paper= =tape= =car track/ramp= = = =Safety Precaution: Take car of the car and don't let it hit you. Be careful to not trip and avoid hitting people with ruler sticks. Wear closed-toe shoes to save your toes.= = = =Procedure:= = We are going to compare the momentums before and after an elastic collision in order to see if momentum is conserved. We will have two cars. These will be measure with an electric balance. The heavier one will go off the ramp and hit a stationary car of a lower mass. We will find the velocity of the heavier car before the collision using a bomber problem off the ramp and table. The velocity of the smaller car before the collision is zero because it is stationary. Then we will do a bomber problem using both cars to find the velocities of the cars after the collision. Using the velocities found, we will fill out a chart and find the momentums using mass times velocity. Last we will compare the momentum before and after to see if momentum was in fact conserved and solve for percent error.= = When doing the first bomber with the purple, heavier car we will mark on paper where it falls using carbon paper. The measurement from the edge of the table to this landing point gives us our average deltaX. We measured the deltaY from the floor to the top of the table. We then filled our x and y chart with these measurements, acceleration in the Y as -9.8, acceleration in the X as 0, and viY as 0. With the kinematic equations (deltaX= vit+.5at^2) we solved for time in the Y which is constant throughout the bomber problem and then used this to solve for the initial velocity in the x direction. With no angles in our experiment this gave us our velocity for the purple car before the collision. = We did a second bomber to solve for the velocity of both cars after the collision. We again used carbon paper to mark and measure the distance from the table to the landing spot. We used the same delta Y and set up two different x and y charts (one for each car). We used the same equation as before to solve for the velocities of both cars after the collision. Next we made our momentum chart. We found the momentum before the collision for the purple car by multiplying its mass times its velocity. The velocity for the other car was 0 because it was stationary making its momentum 0 before the collision. We added the momentum from the purple car to this 0 to give us total momentum before the collision. After the collision we added the momentum of the heavier, purple car (mass times velocity after collision) and the momentum of the lighter, yellow car (mass times velocity after collision) to find the total momentum after the collision. We then compared these two totals to see if momentum was conserved.= = = = = =Conclusions:= =Momentum was in fact conserved. We know this because the momentum before the collision was almost identical to the momentum after the collision. Our percent error was about 3%. We were expecting this result because in an elastic collision momentum is conserved.= = Having any percent error shows us that there was however some error. These errors could be from inaccurate measurements. We measured height and distance using a meter stick, but we should have measured closer to the millimeter instead of rounding as we did to the centimeter. When "Eyeing" the length it is near impossible to be exactly accurate. Also, for each trial since we roughly marked where to let go of the car, the amount of distance it traveled could have changed (distance of track traveled).= = There were a couple things however that we did make sure to do accurately. Measuring the mass with an electric balance was the most accurate way to measure, and while error was inevitable in measuring lengths we made sure the meter stick was lined up exactly with where the car dropped from the table to make it as accurate as possible. Also we did our best to minimize rounding while solving after we collected the data. Lastly we lined up the track horizontally straight against the table so that the cars went of the table in a clean straight line without going off at a slanted angle.=