EBK PHYSICS
5th Edition
ISBN: 8220103026918
Author: Walker
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Textbook Question
Chapter 7, Problem 2PCE
A pendulum bob swings from point II to point III along the circular arc indicated in Figure 7-19. (a) Is the work done on the bob by gravity positive negative, or zero? Explain. (b) Is the work done on the bob by the string positive negative or zero? Explain.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionChapter 7 Solutions
EBK PHYSICS
Ch. 7.1 - Enhance Your Understanding (Answers given at the...Ch. 7.2 - Enhance Your Understanding (Answers given at the...Ch. 7.3 - As an object moves along the positive x axis the...Ch. 7.4 - Enhance Your Understanding (Answers given at the...Ch. 7 - Is it possible to do work on an object that...Ch. 7 - A friend makes the statement, Only the total force...Ch. 7 - A friend makes the statement, A force that is...Ch. 7 - The net work done on a certain object is zero What...Ch. 7 - Give an example of a frictional force doing...Ch. 7 - A ski boat moves with constant velocity Is the net...
Ch. 7 - A package rests on the floor of an elevator that...Ch. 7 - An object moves with constant velocity Is it safe...Ch. 7 - Engine 1 does twice the work of engine 2. Is it...Ch. 7 - Engine 1 produces twice the power of engine 2. Is...Ch. 7 - A pendulum bob swings from point I to point II...Ch. 7 - A pendulum bob swings from point II to point III...Ch. 7 - A farmhand pushes a 26-kg bale of hay 3.9 m across...Ch. 7 - Children in a tree house lift a small dog in a...Ch. 7 - Early one October, you go to a pumpkin patch to...Ch. 7 - The coefficient of kinetic friction between a...Ch. 7 - BIO Peristaltic Work The human snail intestine...Ch. 7 - Predict/Calculate A tow rope, parallel to the...Ch. 7 - A child pulls a friend in a little red wagon with...Ch. 7 - A 57-kg packing crate is pulled with constant...Ch. 7 - Predict/Calculate To clean a floor, a janitor...Ch. 7 - A small plane tows a glider at constant speed and...Ch. 7 - As a snowboarder descends a mountain slope,...Ch. 7 - A young woman on a skateboard is pulled by a rope...Ch. 7 - To keep her dog from running away while she talks...Ch. 7 - Water skiers often ride to one side of the center...Ch. 7 - A pitcher throws a ball at 90 mi/h and the catcher...Ch. 7 - How much work is needed for a 73 kg runner to...Ch. 7 - Skylabs Reentry When Skylab reentered the Earths...Ch. 7 - Predict/Calculate A 9.50-g bullet has a speed of...Ch. 7 - The energy required to increase the speed of a...Ch. 7 - Predict/Explain The work W0 accelerates a car...Ch. 7 - Car A has a mass m and a speed u, car B has a mass...Ch. 7 - Predict/Calculate A 0.14-kg pinecone falls 16 m to...Ch. 7 - In the previous problem (a) how much work was done...Ch. 7 - At t = 1.0s, a 0.55-kg object is tailing with a...Ch. 7 - After hitting a long fly ball that goes over the...Ch. 7 - Predict/Calculate A 1100-kg car coasts on a...Ch. 7 - A 65-kg bicyclist rides his 8 8-kg bicycle with a...Ch. 7 - A block of mass m and speed U collides with a...Ch. 7 - A spring with a force constant of 3.5 104 N/m is...Ch. 7 - Initially sliding with a speed of 4.1 m/s, a...Ch. 7 - The force shown in Figure 7-21 moves an object...Ch. 7 - An object is acted on by the force shown in Figure...Ch. 7 - To compress spring 1 by 0 20 m takes 150 J of...Ch. 7 - Predict/Calculate It takes 180 J of work to...Ch. 7 - The force shown in Figure 7-22 acts on a 1.3-kg...Ch. 7 - A block is acted on by a force that varies as (2.0...Ch. 7 - Section 7-4 Power 42 CE Fore F1 does 5 J of work...Ch. 7 - BIO Climbing the Empire State Building A new...Ch. 7 - Calculate the power output of a 14-mg fly as it...Ch. 7 - An ice cube is placed in a microwave oven. Suppose...Ch. 7 - Your car produces about 34 kw of power to maintain...Ch. 7 - You raise a bucket of water from the bottom of a...Ch. 7 - BIO Salmon Migration As Chinook salmon swim...Ch. 7 - In order to keep a leaking ship from sinking, it...Ch. 7 - Predict/Calculate A kayaker paddles with a power...Ch. 7 - BIO Human-Powered Flight Human-powered aircraft...Ch. 7 - Predict/Calculate Beating to Windward A sailboat...Ch. 7 - Predict/Calculate A grandfather clock is powered...Ch. 7 - Prob. 54PCECh. 7 - CE As the three small sailboats shown in Figure...Ch. 7 - CE Predict/Explain A car is accelerated by a...Ch. 7 - CE Car 1 has four limes the mass of car 2, but...Ch. 7 - BIO Muscle Cells Biological muscle cells can be...Ch. 7 - A small motor runs a lift that raises a load of...Ch. 7 - You push a 67-kg box across a door where the...Ch. 7 - A 1300-kg elevator is lifted at a constant speed...Ch. 7 - CE The work W0 is required to accelerate a car...Ch. 7 - After a tornado a 0.55-g straw was found embedded...Ch. 7 - You throw a glove straight upward to celebrate a...Ch. 7 - The water skier in Figure 7-20 is at an angle of...Ch. 7 - Predict/Calculate A sled with a mass of 5.80 kg is...Ch. 7 - Predict/Calculate A 0.19-kg apple falls from a...Ch. 7 - A boy pulls a bag of baseball bats across a ball...Ch. 7 - At the instant it leaves the players hand after a...Ch. 7 - The force shown in Figure 7-25 acts on an object...Ch. 7 - A Compound Bow A compound bow in archery allows...Ch. 7 - A Compound Versus a Simple Bow The compound bow in...Ch. 7 - Calculate the power output of a 0.42-g spider as...Ch. 7 - Cookie Power To make a batch of cookies, you mix...Ch. 7 - Predict/Calculate A pitcher accelerates a 0.14-kg...Ch. 7 - BIO Brain Power The human brain consumes about 22...Ch. 7 - Meteorite On October 9, 1992, a 27-pound meteorite...Ch. 7 - BIO Powering a Pigeon A pigeon in flight...Ch. 7 - Springs in Series Two springs, with force...Ch. 7 - Springs in Parallel Two springs, with force...Ch. 7 - A block rests on a horizontal frictionless...Ch. 7 - BIO Microraptor gui: The Biplane Dinosaur The...Ch. 7 - BIO Microraptor gui: The Biplane Dinosaur The...Ch. 7 - BIO Microraptor gui: The Biplane Dinosaur The...Ch. 7 - BIO Microraptor gui: The Biplane Dinosaur The...Ch. 7 - Referring to Figure 7-15 Suppose the block has a...Ch. 7 - Predict/Calculate Referring to Figure 7-15 In the...Ch. 7 - Predict/Calculate Referring 10 Example 7-15...
Additional Science Textbook Solutions
Find more solutions based on key concepts
In your own words, briefly distinguish between relative dates and numerical dates.
Applications and Investigations in Earth Science (9th Edition)
1.1 Write a one-sentence definition for each of the following:
a. chemistry
b. chemical
Chemistry: An Introduction to General, Organic, and Biological Chemistry (13th Edition)
Write a balanced chemical equation for each chemical reaction. a. Solid magnesium reacts with aqueous copper(I)...
Introductory Chemistry (6th Edition)
Where are skeletal cartilages located?
Human Anatomy & Physiology (2nd Edition)
27. Consider the reaction.
Express the rate of the reaction in terms of the change in concentration of each of...
Chemistry: Structure and Properties (2nd Edition)
1. ___ Mitosis 2. ___ Meiosis 3. __ Homologous chromosomes 4. __ Crossing over 5. __ Cytokinesis A. Cytoplasmic...
Microbiology with Diseases by Body System (5th Edition)
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.Similar questions
- (a) A force F=(4xi+3yj), where F is in newtons and x and y are in meters, acts on an object as the object moves in the x direction from the origin to x = 5.00 m. Find the work W=Fdr done by the force on the object. (b) What If? Find the work W=Fdr done by the force on the object if it moves from the origin to (5.00 m, 5.00 m) along a straightline path making an angle of 45.0 with the positive x axis. Is the work done by this force dependent on the path taken between the initial and final points?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 shopper pushes a grocery cart 20.0 m at constant speed on level ground, against a 35.0 N frictional force. He pushes in a direction 25.0° below the horizontal. (a) What is the work done on the cart by friction? (b) What is the work done on the cart by the gravitational force? (c) What is the work done on the cart by the shopper? (d) Find the force the shopper exerts, using energy considerations. (e) What is the total work done on the cart?arrow_forward
- “ E=K+Uconstant is a special case of the work energy theorem.” Discuss this statement.arrow_forwardA particle moves in the xy plane (Fig. P9.30) from the origin to a point having coordinates x = 7.00 m and y = 4.00 m under the influence of a force given by F=3y2+x. a. What is the work done on the particle by the force F if it moves along path 1 (shown in red)? b. What is the work done on the particle by the force F if it moves along path 2 (shown in blue)? c. What is the work done on the particle by the force F if it moves along path 3 (shown in green)? d. Is the force F conservative or nonconservative? Explain. FIGURE P9.30 In each case, the work is found using the integral of Fdr along the path (Equation 9.21). W=rtrfFdr=rtrf(Fxdx+Fydy+Fzdz) (a) The work done along path 1, we first need to integrate along dr=dxi from (0,0) to (7,0) and then along dr=dyj from (7,0) to (7,4): W1=x=0;y=0x=7;y=0(3y2i+xj)(dxi)+x=7;y=0x=7;y=4(3y2i+xj)(dyj) Performing the dot products, we get W1=x=0;y=0x=7;y=03y2dx+x=7;y=0x=7;y=4xdy Along the first part of this path, y = 0 therefore the first integral equals zero. For the second integral, x is constant and can be pulled out of the integral, and we can evaluate dy. W1=0+x=7;y=0x=7;y=4xdy=xy|x=7;y=0x=7;y=4=28J (b) The work done along path 2 is along dr=dyj from (0,0) to (0,4) and then along dr=dxi from (0,4) to (7,4): W2=x=0;y=0x=0;y=4(3y2i+xj)(dyj)+x=0;y=4x=7;y=4(3y2i+xj)(dyi) Performing the dot product, we get: W2=x=0;y=0x=0;y=4xdy+x=0;y=4x=7;y=43y2dx Along the first part of this path, x = 0. Therefore, the first integral equals zero. For the second integral, y is constant and can be pulled out of the integral, and we can evaluate dx. W2=0+3y2x|x=0;y=4x=7;y=4=336J (c) To find the work along the third path, we first write the expression for the work integral. W=rtrfFdr=rtrf(Fxdx+Fydy+Fzdz)W=rtrf(3y2dx+xdy)(1) At first glance, this appears quite simple, but we cant integrate xdy=xy like we might have above because the value of x changes as we vary y (i.e., x is a function of y.) [In parts (a) and (b), on a straight horizontal or vertical line, only x or y changes]. One approach is to parameterize both x and y as a function of another variable, say t, and write each integral in terms of only x or y. Constraining dr to be along the desired line, we can relate dx and dy: tan=dydxdy=tandxanddx=dytan(2) Now, use equation (2) in (1) to express each integral in terms of only one variable. W=x=0;y=0x=7;y=43y2dx+x=0;y=0x=7;y=4xdyW=y=0y=43y2dytan+x=0x=7xtandx We can determine the tangent of the angle, which is constant (the angle is the angle of the line with respect to the horizontal). tan=4.007.00=0.570 Insert the value of the tangent and solve the integrals. W=30.570y33|y=0y=4+0.570x22|x=0x=7W=112+14=126J (d) Since the work done is not path-independent, this is non-conservative force. Figure P9.30ANSarrow_forwardAs a simple pendulum swings back and forth, the forces acting on the suspended object are (a) the gravitational force, (b) the tension in the supporting cord, and (c) air resistance. (i) Which of these forces, if any, does no work on the pendulum at any time? (ii) Which of these forces does negative work on the pendulum at all times during its motion?arrow_forward
- Consider a particle on which a force acts that depends on the position of the particle. This force is given by . Find the work done by this force when the particle moves from the origin to a point 5 meters to the right on the x-axis.arrow_forwardIn Figure 5.5 (a)-(d), a block moves to the right in the positive x-direction through the displacement x while under the influence of a force with the same magnitude F. Which of the following is the correct order of the amount of work done by the force F, from most positive to most negative? (a) d, c, a, b (b) c, a, b, d (c) c, a, d, barrow_forwardAs a simple pendulum swings back and forth, the forces acting on the suspended object are the force of gravity, the tension in the supporting cord, and air resistance, (a) Which of these forces, if any, does no work on the pendulum? (b) Which of these forces does negative work at all times during the pendulums motion? (c) Describe the work done by the force of gravity while the pendulum is swinging.arrow_forward
- Repeat the preceding problem, but this time, suppose that the work done by air resistance cannot be ignored. Let the work done by the air resistance when the skier goes from A to B along the given hilly path be —2000 J. The work done by air resistance is negative since the air resistance acts in the opposite direction to the displacement. Supposing the mass of the skier is 50 kg, what is the speed of the skier at point B ?arrow_forwardAn object of mass 10 kg is released at point A, slides to the bottom of the 30 incline, then collides with a horizontal massless spring, compressing it a maximum distance of 0.75 m. (See below.) The spring constant is 500 M/m, the height of the incline is 2.0 m, and the horizontal surface is frictionless. (a) What is the speed of the object at the bottom of the incline? (b) What is the work of friction on the object while it is on the incline? (c) The spring recoils and sends the object back toward the incline. What is the speed of the object when it reaches the base of the incline? (d) What vertical distance does it move back up the incline?arrow_forwardIn a Coyote/Road Runner cartoon clip (https://openstaxcollege.org/l/21coyroadcarcl), a spring expands quickly and sends the coyote into a rock. If the spring extended 5 m and sent the coyote of mass 20 kg to a speed of 15 m/s, (a) what is the spring constant of this spring? (b) If the coyote were sent vertically into the air with the energy given to him by the spring, how high could he go if there were no non-conservative forces?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- College PhysicsPhysicsISBN:9781305952300Author:Raymond A. Serway, Chris VuillePublisher:Cengage LearningCollege PhysicsPhysicsISBN:9781285737027Author:Raymond A. Serway, Chris VuillePublisher:Cengage LearningGlencoe Physics: Principles and Problems, Student...PhysicsISBN:9780078807213Author:Paul W. ZitzewitzPublisher:Glencoe/McGraw-Hill
- Physics for Scientists and Engineers with Modern ...PhysicsISBN:9781337553292Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningUniversity Physics Volume 1PhysicsISBN:9781938168277Author:William Moebs, Samuel J. Ling, Jeff SannyPublisher:OpenStax - Rice UniversityPrinciples of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
College Physics
Physics
ISBN:9781305952300
Author:Raymond A. Serway, Chris Vuille
Publisher:Cengage Learning
College Physics
Physics
ISBN:9781285737027
Author:Raymond A. Serway, Chris Vuille
Publisher:Cengage Learning
Glencoe Physics: Principles and Problems, Student...
Physics
ISBN:9780078807213
Author:Paul W. Zitzewitz
Publisher:Glencoe/McGraw-Hill
Physics for Scientists and Engineers with Modern ...
Physics
ISBN:9781337553292
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
University Physics Volume 1
Physics
ISBN:9781938168277
Author:William Moebs, Samuel J. Ling, Jeff Sanny
Publisher:OpenStax - Rice University
Principles of Physics: A Calculus-Based Text
Physics
ISBN:9781133104261
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
Mechanical work done (GCSE Physics); Author: Dr de Bruin's Classroom;https://www.youtube.com/watch?v=OapgRhYDMvw;License: Standard YouTube License, CC-BY