A train makes a journey in which at a point on its trajectory a speed of 80.0 km / h is measured towards the east, while half an hour later the speed is 65.0 km/h towards the east. Can you calculate the average acceleration in this half hour of travel? a) No, because we do not know the starting position or the final position of that half hour of travel. b) No, because we do not know how the direction of the train changed in the other moments of that half hour of travel. c) Yes, and it has a magnitude of 30.0 km /h?? westward. d) Yes, and it has a magnitude of 30.0 km /h?? to the east.

A train makes a journey in which at a point on its trajectory a speed of 80.0 km / h is measured towards the east, while half an hour later the speed is 65.0 km/h towards the east. Can you calculate the average acceleration in this half hour of travel? a) No, because we do not know the starting position or the final position of that half hour of travel. b) No, because we do not know how the direction of the train changed in the other moments of that half hour of travel. c) Yes, and it has a magnitude of 30.0 km /h?? westward. d) Yes, and it has a magnitude of 30.0 km /h?? to the east.

University Physics Volume 1

18th Edition

ISBN:9781938168277

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

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

Chapter4: Motion In Two And Three Dimensions

Section: Chapter Questions

Problem 32P: A Lockheed Martin F-35 II lighting jet takes off from an aircraft carrier with a runway length of 90...

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