College Physics: A Strategic Approach (3rd Edition)
3rd Edition
ISBN: 9780321879721
Author: Randall D. Knight (Professor Emeritus), Brian Jones, Stuart Field
Publisher: PEARSON
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Textbook Question
Chapter 4, Problem 12CQ
If you are standing still, the upward normal force on you from the floor is equal in magnitude to the weight force that acts on you. But it’s possible to move so that the normal force is greater than your weight. Explain how this could be done.
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Chapter 4 Solutions
College Physics: A Strategic Approach (3rd Edition)
Ch. 4 - If an object is not moving, does that mean that...Ch. 4 - An object moves in a straight line at a constant...Ch. 4 - If you know all of the forces acting on a moving...Ch. 4 - Three arrows are shot horizontally. They have left...Ch. 4 - A carpenter wishes to tighten the heavy head of...Ch. 4 - Internal injuries in vehicular acci-dents may be...Ch. 4 - Heres a great everyday use of the physics...Ch. 4 - Suppose you are an astronaut in deep space, far...Ch. 4 - Jonathan accelerates away from a stop sign. His...Ch. 4 - Normally, jet engines push air out the back of the...
Ch. 4 - If you are standing still, the upward normal force...Ch. 4 - Josh and Taylor, standing face-to-face on...Ch. 4 - A person sits on a sloped hillside. Is it ever...Ch. 4 - Walking without slipping requires a static...Ch. 4 - Figure 4.30 b showed a situation in which the...Ch. 4 - Alyssa pushes to the right on a filing cabinet;...Ch. 4 - A very smart three-year-old child is given a wagon...Ch. 4 - The tire on this drag racer is severely twisted:...Ch. 4 - Suppose that, while in a squatting position, you...Ch. 4 - A block has acceleration a when pulled by a...Ch. 4 - A 5.0 kg block has an acceleration of 0.20 m/s2...Ch. 4 - Tennis balls experience a large drag force. A...Ch. 4 - A group of students is making model cars that will...Ch. 4 - A person gives a box a shove so that it slides up...Ch. 4 - A person is pushing horizontally on a box with a...Ch. 4 - As shown in the chapter, scallops use jet...Ch. 4 - Dave pushes his four-year-old son Thomas across...Ch. 4 - Figure Q4.29 shows block A sitting on top of block...Ch. 4 - Whiplash injuries during an automobile accident...Ch. 4 - An automobile has a head-on collision. A passenger...Ch. 4 - In a head-on collision, an infant is much safer in...Ch. 4 - Problems 4 through 6 show two forces acting on an...Ch. 4 - Problems 4 through 6 show two forces acting on an...Ch. 4 - Problems 4 through 6 show two forces acting on an...Ch. 4 - A mountain climber is hanging from a vertical...Ch. 4 - You look up from your textbook and observe a...Ch. 4 - A baseball player is sliding into second base....Ch. 4 - A jet plane is speeding down the runway during...Ch. 4 - A skier is sliding down a 15 slope. Friction is...Ch. 4 - A falcon is hovering above the ground, then...Ch. 4 - Figure P4.13 shows an acceleration-versus-force...Ch. 4 - A constant force applied to object A causes it to...Ch. 4 - A compact car has a maximum acceleration of 4.0...Ch. 4 - A constant force is applied to an object, causing...Ch. 4 - A constant force is applied to an object, causing...Ch. 4 - A man pulling an empty wagon causes it to...Ch. 4 - A car has a maximum acceleration of 5.0 m/s2 What...Ch. 4 - Scallops eject water from their shells to provide...Ch. 4 - Figure P4.21 shows an objects...Ch. 4 - In t-ball, young players use a bat to hit a...Ch. 4 - Two children fight over a 200 g stuffed bear. The...Ch. 4 - A 1500 kg car is traveling along a straight road...Ch. 4 - The motion of a very massive object can be...Ch. 4 - Very small forces can have tremendous effects on...Ch. 4 - Problems 27 through 29 show a free-body diagram....Ch. 4 - Problems 27 through 29 show a free-body diagram....Ch. 4 - Problems 27 through 29 show a free-body diagram....Ch. 4 - Problems 30 through 38 describe a situation. For...Ch. 4 - Problems 30 through 38 describe a situation. For...Ch. 4 - Problems 30 through 38 describe a situation. For...Ch. 4 - Problems 30 through 38 describe a situation. For...Ch. 4 - Problems 30 through 38 describe a situation. For...Ch. 4 - Problems 30 through 38 describe a situation. For...Ch. 4 - Problems 30 through 38 describe a situation. For...Ch. 4 - Problems 30 through 38 describe a situation. For...Ch. 4 - Problems 30 through 38 describe a situation. For...Ch. 4 - Three ice skaters, numbered 1, 2, and 3, stand in...Ch. 4 - A girl stands on a sofa. Identify all the...Ch. 4 - A car is skidding to a stop on a level stretch of...Ch. 4 - Squid use jet propulsion for rapid escapes. A...Ch. 4 - Redraw the motion diagram shown in Figure P4.43,...Ch. 4 - Redraw the motion diagram shown in Figure P4.44,...Ch. 4 - Redraw the motion diagram shown in Figure P4.45,...Ch. 4 - Redraw the motion diagram shown in Figure P4.46,...Ch. 4 - A student draws the flawed free-body diagram shown...Ch. 4 - A student draws the flawed free-body diagram shown...Ch. 4 - Problems 49 through 61 describe a situation. For...Ch. 4 - Problems 49 through 61 describe a situation. For...Ch. 4 - Problems 49 through 61 describe a situation. For...Ch. 4 - Problems 49 through 61 describe a situation. For...Ch. 4 - Problems 49 through 61 describe a situation. For...Ch. 4 - Problems 49 through 61 describe a situation. For...Ch. 4 - Problems 49 through 61 describe a situation. For...Ch. 4 - Problems 49 through 61 describe a situation. For...Ch. 4 - Problems 49 through 61 describe a situation. For...Ch. 4 - Problems 49 through 61 describe a situation. For...Ch. 4 - Problems 49 through 61 describe a situation. For...Ch. 4 - Problems 49 through 61 describe a situation. For...Ch. 4 - A bag of groceries is on the back seat of your car...Ch. 4 - A car has a mass of 1500 kg. If the driver applies...Ch. 4 - A rubber ball bounces. Wed like to understand how...Ch. 4 - If a car stops suddenly, you feel thrown forward....Ch. 4 - The fastest pitched baseball was clocked at 46...Ch. 4 - The froghopper, champion leaper of the insect...Ch. 4 - A beach ball is thrown straight up, and some time...Ch. 4 - If your car is stuck in the mud and you dont have...Ch. 4 - If your car is stuck in the mud and you don't have...Ch. 4 - If your car is stuck in the mud and you don't have...Ch. 4 - If your car is stuck in the mud and you don't have...
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