A speeding train (with mass 444,000 kg) is moving east with speed 88.9 m/s. Superman (with mass 90.7 kg) needs to stop the train, (so it doesn't fly off the edge of a cliff!) so he flies directly west toward the train. When he reaches the train, he holds it tightly, and they come to a complete stop in 3.25 s. Coordinate system: • east is in the positive x direction • west is in the negative x direction Question 1 What kind of collision is this? elastic inelastic Question 2 What is the sign of the initial momentum of the train? O positive negative Question 3 What is the sign of the initial momentum of Superman? O positive O negative

A speeding train (with mass 444,000 kg) is moving east with speed 88.9 m/s. Superman (with mass 90.7 kg) needs to stop the train, (so it doesn't fly off the edge of a cliff!) so he flies directly west toward the train. When he reaches the train, he holds it tightly, and they come to a complete stop in 3.25 s. Coordinate system: • east is in the positive x direction • west is in the negative x direction Question 1 What kind of collision is this? elastic inelastic Question 2 What is the sign of the initial momentum of the train? O positive negative Question 3 What is the sign of the initial momentum of Superman? O positive O negative

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 96A

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