You have been hired to investigate a car accident which occurred when the driver of one car was stopped at a stoplight. The driver claims that she was idling at the stoplight and her car was in neutral when she was rear-ended by another car. You have data on the tire skid marks of the two cars, which can help you determine their velocities. You also know the make and model of each car, which helps you determine their masses. To get a handle on the basic physics involved, you want to model the situation with a simple laboratory experiment. Given the masses of the cars, and the initial velocity of one car, can you predict the final velocities of the two cars in a perfectly inelastic collision? Let's assume two objects with masses m1 and m2 are initially moving with velocities v1 and v2 respectively. A perfectly inelastic collision is one where the two objects stick together after the collision. Thus, after the collisions both objects move with speed vf 1. What quantity or quantities are conserved in this collision? (That is, what physical quantity or quantities do not change as a result of the collision)? Explain. I know it's momentum but can you explain it a little more? 2. Using the conservation law(s) you identified in the previous part, write one ore more equations relating the masses m1, m2 , initial velocities v1,v2 and the final velocity vf . 3. Solve your equation(s) for vf . You should now have a prediction equation for the final velocity of the two objects if you know their initial masses and velocities.
You have been hired to investigate a car accident which occurred when the driver of one car was stopped at a stoplight. The driver claims that she was idling at the stoplight and her car was in neutral when she was rear-ended by another car. You have data on the tire skid marks of the two cars, which can help you determine their velocities. You also know the make and model of each car, which helps you determine their masses. To get a handle on the basic physics involved, you want to model the situation with a simple laboratory experiment. Given the masses of the cars, and the initial velocity of one car, can you predict the final velocities of the two cars in a perfectly inelastic collision?
Let's assume two objects with masses m1 and m2 are initially moving with velocities v1 and v2 respectively.
A perfectly inelastic collision is one where the two objects stick together after the collision. Thus, after the collisions both objects move with speed vf
1. What quantity or quantities are conserved in this collision? (That is, what physical quantity or quantities do not change as a result of the collision)? Explain. I know it's momentum but can you explain it a little more?
2. Using the conservation law(s) you identified in the previous part, write one ore more equations relating the masses m1, m2 , initial velocities v1,v2 and the final velocity vf .
3. Solve your equation(s) for vf . You should now have a prediction equation for the final velocity of the two objects if you know their initial masses and velocities.
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