Physics (5th Edition)
5th Edition
ISBN: 9780321976444
Author: James S. Walker
Publisher: PEARSON
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Textbook Question
Chapter 8, Problem 39PCE
You ride your bicycle down a hill, maintaining a constant speed the entire time. (a) As you ride, does the gravitational potential energy of the you-bike-Earth system increase, decrease, or stay the same? Explain. (b) Does the kinetic energy of you and your bike increase, decrease, or stay the same? Explain. (c) Does the mechanical energy of the you-bike-Earth system increase, decrease, or stay the same? Explain.
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Chapter 8 Solutions
Physics (5th Edition)
Ch. 8.1 - 1. In Figure 8-8, the work done by a conservative...Ch. 8.2 - 1. The work done by a conservative force on a...Ch. 8.3 - A system with only conservative forces acting on...Ch. 8.4 - 4. A system is acted on by more than one force,...Ch. 8.5 - A system consists of an object moving along the x...Ch. 8 - Is it possible for the kinetic energy of an object...Ch. 8 - If the stretch of a spring is doubled, the force...Ch. 8 - When a mass is placed on top of a vertical spring,...Ch. 8 - If a spring is stretched so far that it is...Ch. 8 - An object is thrown upward to a person on a roof....
Ch. 8 - It is a law of nature that the total energy of the...Ch. 8 - Discuss the venous energy conversions that occur...Ch. 8 - Discuss the nature of the work done by the...Ch. 8 - It the force on an object is zero, does that mean...Ch. 8 - When a ball is thrown upward, its mechanical...Ch. 8 - When a ball is thrown upward, it spends the same...Ch. 8 - The work done by a conservative force is indicated...Ch. 8 - 2. Calculate the work done by gravity as a 3.2-kg...Ch. 8 - Calculate the work done by friction as a 37-kg box...Ch. 8 - Predict/Calculate A 2.8-kg block is attached to a...Ch. 8 - Predict/Calculate (a) Calculate the work done by...Ch. 8 - In the system shown in Figure 8-26, suppose the...Ch. 8 - Predict/Explain Ball 1 is thrown to the ground...Ch. 8 - A mass is attached to the bottom of a vertical...Ch. 8 - Find the gravitational potential energy of an...Ch. 8 - A student lifts a 1.42-kg book from her desk to a...Ch. 8 - At the local ski slope, an 82.0-kg skier rides a...Ch. 8 - BIO The Wing of the Hawkmoth Experiments performed...Ch. 8 - Predict/Calculate A vertical spring stores 0.962 J...Ch. 8 - Pushing on the pump of a soap dispenser compresses...Ch. 8 - BIO Mantis Shrimp Smasher A peacock mantis shrimp...Ch. 8 - Predict/Calculate The work required to stretch a...Ch. 8 - A 0.33-kg pendulum bob is attached to a string 1.2...Ch. 8 - Prob. 18PCECh. 8 - Prob. 19PCECh. 8 - For an object moving along the x axis, the...Ch. 8 - At an amusement park, a swimmer uses a water side...Ch. 8 - Prob. 22PCECh. 8 - A skateboarder at a skate park rides along the...Ch. 8 - Three balls are thrown upward with the same...Ch. 8 - A 0.21-kg apple falls from a tree to the ground,...Ch. 8 - Predict/Calculate A 2.9-kg block slides with a...Ch. 8 - A 0.26-kg rock is thrown vertically upward from...Ch. 8 - A 1 40-kg block sides with a speed of 0.950 m/s on...Ch. 8 - A 5.76-kg rock is dropped and allowed to fall...Ch. 8 - Predict/Calculate Suppose the pendulum bob m...Ch. 8 - The two masses in the Atwoods machine shown in...Ch. 8 - In the previous problem, suppose the masses have...Ch. 8 - Prob. 33PCECh. 8 - Catching a wave, a 77-kg surfer starts with a...Ch. 8 - At a playground, a 19-kg child plays on a slide...Ch. 8 - Starting at rest at the edge of a swimming pool, a...Ch. 8 - A 22,000-kg airplane lands with a speed of 64 m/s...Ch. 8 - A78-kg skateboarder grinds down a hubba ledge that...Ch. 8 - You ride your bicycle down a hill, maintaining a...Ch. 8 - A 111-kg seal at an amusement park slides from...Ch. 8 - A 1.9-kg rock is released from rest at the surface...Ch. 8 - A 1250-kg car drives up a hill that is 16.2 m...Ch. 8 - The Outlaw Run roller coaster in Branson,...Ch. 8 - A 1.80-kg block slides on a rough horizontal...Ch. 8 - Figure 8-34 shows a potential energy curve as a...Ch. 8 - An object moves along the x axis, subject to the...Ch. 8 - A 1.34-kg object moves along the x axis, subject...Ch. 8 - The potential energy of a particle moving along...Ch. 8 - A block of mass m = 0.88 kg is connected to a...Ch. 8 - A ball of mass m = 0.75 kg is thrown straight...Ch. 8 - Figure 8-35 depicts the potential energy of a...Ch. 8 - Figure 8-35 depicts the potential energy of a...Ch. 8 - CE You and a friend both solve a problem involving...Ch. 8 - CE A particle moves under the influence of a...Ch. 8 - A sled slides without friction down a small,...Ch. 8 - A 74 Kg skier encounters a dip in the snows...Ch. 8 - Running Shoes The soles of a popular make of...Ch. 8 - Nasal Strips The force required to flex a nasal...Ch. 8 - The water slide shown in Figure 8-37 ends at a...Ch. 8 - A skateboarder starts at point A in Figure 8-38...Ch. 8 - The Crash of Skylab NASAs Skylab, the largest...Ch. 8 - BIO Bird Tendons Several studies indicate that the...Ch. 8 - In the Atwoods machine of Problem 31, the mass m2...Ch. 8 - A 6.60-kg block slides with an initial speed of...Ch. 8 - Jeff of the Jungle swings on a 7.6-m vine that...Ch. 8 - A 1.9-kg block slides down a frictionless ramp, as...Ch. 8 - Suppose the ramp in Figure 8-40 is not motionless....Ch. 8 - BIO Compressing the Ground A running track at...Ch. 8 - BIO A Fleas Jump The resilin in the body of a flea...Ch. 8 - Predict/Calculate Tension at the Bottom A ball of...Ch. 8 - An ice cube is placed on top of an overturned...Ch. 8 - Predict/Calculate The two blocks shown in Figure...Ch. 8 - Predict/Calculate Loop-the-Loop (a) A block of...Ch. 8 - Figure 8-45 shows a 1.75-kg block at rest on a...Ch. 8 - In Figure 8-45 a 1.2-kg block is held at rest...Ch. 8 - BIO The Flight of the Dragonflies Of all the...Ch. 8 - BIO The Flight of the Dragonflies Of all the...Ch. 8 - BIO The Flight of the Dragonflies Of all the...Ch. 8 - BIO The Flight of the Dragonflies Of all the...Ch. 8 - Predict/Calculate Referring to Example 8-12...Ch. 8 - Referring to Example 8-12 Suppose the block is...Ch. 8 - Referring to Example 8-17 suppose we would like...
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- . In the annual Empire State Building race, contestants run up 1,575 steps to a height of 1,050 ft. In 2003, Australian Paul Crake completed the race in a record time of 9 min and 33 S, Mr., Crake weighed 143 lb (65 kg) , (a) How much work did Mr., Crake do in reaching the top of the building? (b) What was his average power output (in ft-lb/s and in hp)?arrow_forward(a) Can the kinetic energy of a system be negative? (b) Can the gravitational potential energy of a system be negative? Explain.arrow_forwardA particle moves in one dimension under the action of a conservative force. The potential energy of the system is given by the graph in Figure P8.55. Suppose the particle is given a total energy E, which is shown as a horizontal line on the graph. a. Sketch bar charts of the kinetic and potential energies at points x = 0, x = x1, and x = x2. b. At which location is the particle moving the fastest? c. What can be said about the speed of the particle at x = x3? FIGURE P8.55arrow_forward
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