** 20. A string exerts an upward tension force of 45 N on a 5-kg blo ck as it slowly lowers the block a distance of 4 meters. Tb 45 N a) Find the total external work done on the block-earth system by the tension in the string as the block drops the 4 meters. 5 kg b) Find the change in gravitational potential energy for the block-earth system as the block drops 4 meters c) Find the change in kinetic energy for the block-earth system as the block drops 4 meters

** 20. A string exerts an upward tension force of 45 N on a 5-kg blo ck as it slowly lowers the block a distance of 4 meters. Tb 45 N a) Find the total external work done on the block-earth system by the tension in the string as the block drops the 4 meters. 5 kg b) Find the change in gravitational potential energy for the block-earth system as the block drops 4 meters c) Find the change in kinetic energy for the block-earth system as the block drops 4 meters

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter7: Conservation Of Energy

Section: Chapter Questions

Problem 5OQ: Answer yes or no to each of the following questions. (a) Can an objectEarth system have kinetic...

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