= = 18.0 m/s to the east. 2. A 1200-kg car traveling initially at vci = 25.0 m/s in an easterly direction crashes into the back of a 9000-kg truck moving in the same direction at VTi 20.0 m/s, as shown in the figure below. The velocity of the car immediately after the collision is vcf (a) What is the velocity of the truck immediately after the collision? (b) What is the change in mechanical energy of the car-truck system in the collision? (c) Does the mechanical energy of the car-truck system increase, decrease, or unchange? VCi vcf Before After

= = 18.0 m/s to the east. 2. A 1200-kg car traveling initially at vci = 25.0 m/s in an easterly direction crashes into the back of a 9000-kg truck moving in the same direction at VTi 20.0 m/s, as shown in the figure below. The velocity of the car immediately after the collision is vcf (a) What is the velocity of the truck immediately after the collision? (b) What is the change in mechanical energy of the car-truck system in the collision? (c) Does the mechanical energy of the car-truck system increase, decrease, or unchange? VCi vcf Before After

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter9: Linear Momentum And Collisions

Section: Chapter Questions

Problem 92AP: A car crashes into a large tree that does not move. The car goes from 30 m/s to 0 in 1.3 m. (a) What...

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The figure below shows a bullet of mass 200 g traveling horizontally towards the east with speed 400 m/s, which strikes a block of mass 1.5 kg that is initially at rest on a frictionless table. After striking the block, the bullet is embedded in the block and the block and the bullet move together as one unit. a. What is the magnitude and direction of the velocity of the block/bullet combination immediately after the impact? b. What is the magnitude and direction of the impulse by the block on the bullet? c. What is the magnitude and direction of the impulse from the bullet on the block? d. If it took 3 ms for the bullet to change the speed from 400 m/s to the final speed after impact, what is the average force between the block and the bullet during this time?
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