University Physics (14th Edition)
14th Edition
ISBN: 9780133969290
Author: Hugh D. Young, Roger A. Freedman
Publisher: PEARSON
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Chapter 4, Problem 4.47P
CP Jumping to the Ground. A 75.0-kg man steps off a platform 3.10 m above the ground. He keeps his legs straight as he falls, but his knees begin to bend at the moment his feet touch the ground; treated as a particle, he moves an additional 0.60 m before coming to rest. (a) What is his speed at the instant his feet touch the ground? (b) If we treat the man as a particle, what is his acceleration (magnitude and direction) as he slows down, if the acceleration is assumed to be constant? (c) Draw his free-body diagram. In terms of the forces on the diagram, what is the net force on him? Use Newton’s laws and the results of part (b) to calculate the average force his feet exert on the ground while he slows down. Express this force both in newtons and as a multiple of his weight.
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Chapter 4 Solutions
University Physics (14th Edition)
Ch. 4 - Can a body be in equilibrium when only one force...Ch. 4 - A ball thrown straight up has zero velocity at its...Ch. 4 - A helium balloon hovers in midair, neither...Ch. 4 - When you fly in an airplane at night in smooth...Ch. 4 - If the two ends of a rope in equilibrium are...Ch. 4 - You tie a brick lo the end of a rope and whirl the...Ch. 4 - When a car stops suddenly, the passengers tend to...Ch. 4 - Some people say that the force of inertia (or...Ch. 4 - A passenger in a moving bus with no windows...Ch. 4 - Suppose you chose the fundamental physical...
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