Recall: work done equals change in kinetic energy 4. 4) On a frictionless surface, a block with mass M1 =0.50 kg moving at 4 m/s to the right collides with a mass M2= 0.20kg block moving to the left at 2m/s. The bodies move along the x-axis only. a) If the two blocks stick together after the collision, what is the final velocity (magnitude and direction? b) How much mechanical energy is lost? c) If the collision lasts for 30ms, find the average force. 5. A 72-kg athlete starts from rest and then sprints on a level track, reaching a final speed of 6.3m/s after 12 seconds. a) Calculate the work done. b) What was her average mechanical power? 6. A spring exerts a force of 100 N when compressed 0.15m. a) Determine the spring constant and calculate how much potential energy is stored in the spring, if it is now compressed 0.20 m? b) The spring compressed 0.20m, is used to launch a 0.6 kg ball horizontally. What is the maximum speed with which the ball can be launched?

Recall: work done equals change in kinetic energy 4. 4) On a frictionless surface, a block with mass M1 =0.50 kg moving at 4 m/s to the right collides with a mass M2= 0.20kg block moving to the left at 2m/s. The bodies move along the x-axis only. a) If the two blocks stick together after the collision, what is the final velocity (magnitude and direction? b) How much mechanical energy is lost? c) If the collision lasts for 30ms, find the average force. 5. A 72-kg athlete starts from rest and then sprints on a level track, reaching a final speed of 6.3m/s after 12 seconds. a) Calculate the work done. b) What was her average mechanical power? 6. A spring exerts a force of 100 N when compressed 0.15m. a) Determine the spring constant and calculate how much potential energy is stored in the spring, if it is now compressed 0.20 m? b) The spring compressed 0.20m, is used to launch a 0.6 kg ball horizontally. What is the maximum speed with which the ball can be launched?

Glencoe Physics: Principles and Problems, Student Edition

1st Edition

ISBN:9780078807213

Author:Paul W. Zitzewitz

Publisher:Paul W. Zitzewitz

Chapter9: Momentum And Its Conservation

Section: Chapter Questions

Problem 70A

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