10 The Momentum of Curling Experiment PDF

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Experiment: Momentum and Collisions on a Curling Rink Directions and Reminders  Remember that we will be meeting at the Toronto Cricket and Curling club at 8:30 am.  Dress warmly and remember to bring clean shoes and do not wear jeans.  Before we begin this laboratory remember that we are guests at the Toronto Cricket and Curling Club. Please abide by any rules that are announced. Directions via TTC (The Address is 141 Wilson)  From Wilson station the 96A bus runs East. Stop at Belgrave ave.  From York Mills station the 96A and 165 run West. Stop at Belgrave ave. Purpose: to verify the laws of momentum, and investigate changes in kinetic energy. Materials: - 1 stopwatch - Measuring tape - A curling rink and some curling rocks Before you Start: You will need to define directions to use for your vectors in the lab. Identify the North, East, South and West side of the curling rink and use these to define your directions. Procedure Part A: Determine the rate of deceleration on our curling rink. (1) Find a clear stretch on the rink to perform this and subsequent parts of the procedure. (2) Choose a starting point from which the rocks will be released. Most curling rinks have lines on them so this should be fairly easy. (3) One member of the group should now take a rock and slide it down the rink, with a straight-line motion. They should release it the moment the front of the rock touches the starting line. At this same moment in time another member of the group should start timing with the stopwatch. (4) Watch the motion of the rock. The timer should be stopped at the exact moment the rock comes to rest. Record this time. (5) Measure the distance from the starting line to the front of the rock at rest. Record the distance. (6) Repeat steps 3-5 at least three times. Analysis Part A: (1) Use a diagram and chart to illustrate all the data that you obtained in part A. (2) Using the data from procedure part A determine the rate at which the rocks decelerate on the ice. Take an average of these three accelerations; you will be using this average for further analysis throughout the lab. Accept it as the rate at which all rocks decelerate on the ice. Be sure to show how you got the formula that you are using to calculate the acceleration. Procedure Part B: Momentum in Two Dimensions (1) From your starting position look down the rink and choose another point to be your collision position. Measure the distance between the starting position and the collision position and record this value. (2) Place another rock at the collision position and send a curling rock down the rink so that it experiences a collision with this rock, ensuring that both rocks move off in different directions after the collision. The timer should start the stopwatch at the moment the rock crosses the starting position and stop it at the moment of impact. (3) It is not necessary to time the rocks after they have collided, however, do not disrupt their motion, and allow them to come to a complete stop before continuing. (4) Measure the distance from the position of each rock at the point of impact to their final position at rest. (5) You should also record the direction of travel of each rock after the collision, relative to the original direction of travel of the incident rock.

Analysis Part B: (1) Use a diagram to illustrate all the data that you obtained in part B. (2) Determine the velocity of the incident rock at impact as well as the velocities of both rocks after impact, do not use the conservation of momentum at this point to do this. This will take some thinking, but it is possible to do it accurately using the data acquired above. (3) Verifying the Conservation of Momentum (a) Write out the conservation of momentum equation applicable to this collision. Simplify it without plugging in any numbers. You will next attempt to verify this equation using your data. (b) We will take the initial velocity of the incident rock at impact and the angles after the collision to be accepted values. Use these values and the conservation of momentum to determine the speed of each rock after the collision. Include a momentum vector diagram in your calculations. (c) Compare the speeds of the rocks after the collision that you determined using the conservation of momentum, with the speeds of the rocks after the collision that you determine using your data in (2). Use a percentage difference or percentage error calculation to do this. (d) Was the law of conservation of momentum verified? Explain why or why not using your results. Be sure to describe which speeds are being compared in (c) in your explanation. Identify which speeds are the theoretical and which speeds are the experimental. (4) Comparing the Change in Momentum of Both Rocks (a) Using the angles, the velocity of the incident rock at impact and the velocities of both rocks after impact that you determined in (2) calculate the change in momentum of the incident rock and the change in momentum of the rock that was hit (this will involve a vector subtraction). Include diagrams in your calculations illustrating the momentum vectors and change in momentum vectors for each rock. (b) Compare the change in momentum of the incident rock with the change in momentum of the rock that was hit. Remember to compare both their magnitudes and their directions. To help compare the directions use a vector diagram. What can you conclude about the change in momentum of the incident rock as compare to the rock that was hit? Why does this result make sense, or not make sense, in relation to the law of conservation of momentum? Explain. (5) Determine the total kinetic energy of the system before and after the collision. (Be sure to use the speeds that you determined in (2) to do this.) Use these values to determine the total change in kinetic energy during the collision. Would you consider this to be an example of an elastic or inelastic collision? Procedure Part C: Momentum in Two Dimensions (Two Different Masses) (1) Place a junior curling rock at the collision point, and repeat procedure part B for a two dimensional collision involving two masses. Be sure to record all the same data as you did in part B. Analysis Part C: (1) Use a diagram to illustrate all the data that you obtained in part C. (2) Determine the velocity of the incident rock at impact as well as the velocities of both rocks after impact using the data that you obtained. Do not use the conservation of momentum to do this part. (3) Determining the Mass of The Junior Rock (a) Write out the conservation of momentum equation applicable to this collision. (b) Use your conservation of momentum equation and the data you recorded to determine the mass of the junior rock. You will have to use two of the velocities that you determined in (2) in order to do this. Include a momentum vector diagram in your calcuations....