University Physics with Modern Physics (14th Edition)
14th Edition
ISBN: 9780321973610
Author: Hugh D. Young, Roger A. Freedman
Publisher: PEARSON
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Textbook Question
Chapter 4, Problem 4.60PP
The forces on a dancer can be measured directly when a dancer performs a jump on a force plate that measures the force between her feet and the ground. A graph of force versus time throughout a vertical jump performed on a force plate is shown in Fig. P4.60. What is happening at 0.4 s ’The dancer is (a) bending her legs so that her body is accelerating downward; (b) pushing her body up with her legs and is almost ready to leave the ground; (c) in the air and at the top of her jump; (d) landing and her feet have just touched the ground.
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Chapter 4 Solutions
University Physics with Modern Physics (14th Edition)
Ch. 4.1 - Figure 4.5 shows a force F acting on a crate. With...Ch. 4.2 - In which of the following situations is there zero...Ch. 4.3 - Rank the following situations in order of the...Ch. 4.4 - Prob. 4.4TYUCh. 4.5 - You are driving a car on a country road when a...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...Ch. 4 - Why is the earth only approximately an inertial...Ch. 4 - Does Newtons second law hold true for an observer...Ch. 4 - Some students refer to the quantity ma as the...Ch. 4 - The acceleration of a falling body is measured in...Ch. 4 - You can play catch with a softball in a bus moving...Ch. 4 - Students sometimes say that the force of gravity...Ch. 4 - Why can it hurt your foot more to kick a big rock...Ch. 4 - Its not the fall that hurts you; its the sudden...Ch. 4 - A person can dive into water from a height of 10 m...Ch. 4 - Why are cars designed to crumple in front and back...Ch. 4 - When a string barely strong enough lifts a heavy...Ch. 4 - A large crate is suspended from the end of a...Ch. 4 - Which feels a greater pull due to the earths...Ch. 4 - Why is it incorrect to say that 1.0 kg equals 2.2...Ch. 4 - A horse is hitched to a wagon. 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Basketball player...Ch. 4 - CP An advertisement claims that a particular...Ch. 4 - BIO Human Biomechanics. The fastest pitched...Ch. 4 - BIO Human Biomechanics. The fastest served tennis...Ch. 4 - Two crates, one with mass 4.00 kg and the other...Ch. 4 - CP Two blocks connected by a light horizontal rope...Ch. 4 - CALC To study damage to aircraft that collide with...Ch. 4 - CP A 6.50-kg instrument is hanging by a vertical...Ch. 4 - BIO Insect Dynamics. The froghopper (Philaenus...Ch. 4 - A loaded elevator with very worn cables has a...Ch. 4 - CP After an annual checkup, you leave your...Ch. 4 - CP A nail in a pine board stops a 4.9-N hammer...Ch. 4 - CP Jumping to the Ground. A 75.0-kg man steps off...Ch. 4 - The two blocks in Fig. P4.48 are connected by a...Ch. 4 - CP Boxes A and B are connected to each end of a...Ch. 4 - CP Extraterrestrial Physics. 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