You throw a ball from the ground UP to someone leaning out a second story window. (a) During the motion of the ball, does gravity do positive, negative, or zero work on the ball? Explain your answer. (b) During this same motion of the ball (up from the ground to the window above), how does the kinetic energy of the ball change (increase, decrease, or stay the same)? (c) What is the connection between this change in KE and the work done by gravity? (d) The same ball is now dropped back from the second story window down to the ground. As the ball falls, does gravity do positive, negative, or zero work on it? (e) How does this affect the kinetic energy of the ball?

You throw a ball from the ground UP to someone leaning out a second story window. (a) During the motion of the ball, does gravity do positive, negative, or zero work on the ball? Explain your answer. (b) During this same motion of the ball (up from the ground to the window above), how does the kinetic energy of the ball change (increase, decrease, or stay the same)? (c) What is the connection between this change in KE and the work done by gravity? (d) The same ball is now dropped back from the second story window down to the ground. As the ball falls, does gravity do positive, negative, or zero work on it? (e) How does this affect the kinetic energy of the ball?

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

Chapter6: Energy Of A System

Section: Chapter Questions

Problem 1CQ

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