Physics (5th Edition)
5th Edition
ISBN: 9780321976444
Author: James S. Walker
Publisher: PEARSON
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Chapter 11, Problem 7PCE
At the local playground, a 21-kg child sits on the right end of a horizontal teeter-totter, 1.8 m from the pivot point. On the left side of the pivot an adult pushes straight down on the teeter-totter with a force of 151 N. In which direction (clockwise or counterclockwise) does the teeter-totter rotate if the adult applies the force at a distance of (a) 3.0 m, (b) 2.5 m, or (c) 2.0 m from the pivot?
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At the local playground, a 21-kg child sits on the right end ofa horizontal teeter-totter, 1.8 m from the pivot point. On the leftside of the pivot an adult pushes straight down on the teeter-totterwith a force of 151 N. In which direction (clockwise or counterclockwise) does the teeter-totter rotate if the adult applies the forceat a distance of (a) 3.0 m, (b) 2.5 m, or (c) 2.0 m from the pivot?
40 KN
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60 KN
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16 m 12 m 8 m
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The three-step pulley is
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(b) determine the
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CCW = positive
CW = negative
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Chapter 11 Solutions
Physics (5th Edition)
Ch. 11.1 - A bicycle wheel is mounted on an axle, as shown in...Ch. 11.2 - Consider two objects with the following...Ch. 11.3 - A Physics sign is supported symmetrically by two...Ch. 11.4 - A mobile made from three piggy banks (A, B, C) is...Ch. 11.5 - Prob. 5EYUCh. 11.6 - Consider two objects with the following...Ch. 11.7 - Prob. 7EYUCh. 11.8 - In system 1, a torque of 20 N m acts through an...Ch. 11.9 - The angular velocity of the spinning bicycle wheel...Ch. 11 - Two forces produce the same torque. Does it follow...
Ch. 11 - A car pitches down in front when the brakes are...Ch. 11 - A tightrope walker uses a long pole to aid in...Ch. 11 - When a motorcycle accelerates rapidly from a stop...Ch. 11 - Give an example of a system in which the net...Ch. 11 - Give an example of a system in which the net force...Ch. 11 - Is the normal force exerted by the ground the same...Ch. 11 - Give two everyday examples of objects that are not...Ch. 11 - Give two everyday examples of objects that are in...Ch. 11 - Can an object have zero translational acceleration...Ch. 11 - Stars form when a large rotating cloud of gas...Ch. 11 - What purpose does the tail rotor on a helicopter...Ch. 11 - Is it possible to change the angular momentum of...Ch. 11 - Suppose a diver springs into the air with no...Ch. 11 - To tighten a spark plug, it is recommended that a...Ch. 11 - Pulling a Weed The gardening tool shown in Figure...Ch. 11 - A person slowly lowers a 3.6-kg crab trap over the...Ch. 11 - A squirrel-proof bird feeder has a lever that...Ch. 11 - At one position during its cycle, the foot pushes...Ch. 11 - BIO Predict/Calculate Force to Hold a Baseball A...Ch. 11 - At the local playground, a 21-kg child sits on the...Ch. 11 - Predict/Explain Consider the pulley-block systems...Ch. 11 - Suppose a torque rotates your body about one of...Ch. 11 - A torque of 0.97 N m is applied to a bicycle...Ch. 11 - When a ceiling fan rotating with an angular speed...Ch. 11 - When the play button is pressed, a CD accelerates...Ch. 11 - A person holds a ladder horizontally at its...Ch. 11 - A 0.180-kg wooden rod is 1.25 m long and pivots at...Ch. 11 - Predict/Calculate A wheel on a game show is given...Ch. 11 - The L-shaped object in Figure 11-41 consists of...Ch. 11 - The L-shaped object described in the previous...Ch. 11 - A motorcycle accelerates from rest, and both the...Ch. 11 - Predict/Calculate A torque of 13 N m is applied...Ch. 11 - Predict/Explain Suppose the person in Example...Ch. 11 - A string that passes over a pulley has a 0.321-kg...Ch. 11 - To loosen the lid on a jar of jam 7.6 cm in...Ch. 11 - BIO Predict/Calculate Referring to the person...Ch. 11 - Prob. 24PCECh. 11 - Prob. 25PCECh. 11 - Predict/Calculate A schoolyard teeter-totter with...Ch. 11 - A 0.122-kg remote control 23.0 cm long rests on a...Ch. 11 - Predict/Calculate A 0.16-kg meterstick is held...Ch. 11 - Prob. 29PCECh. 11 - A uniform metal rod, with a mass of 2.0 kg and a...Ch. 11 - Prob. 31PCECh. 11 - In Figure 11-46 two acrobats perform a balancing...Ch. 11 - BIO Forces in the Foot In Figure 11-47 we see the...Ch. 11 - A stick with a mass of 0.214 kg and a length of...Ch. 11 - Prob. 35PCECh. 11 - If the cat in Example 11-9 has a mass of 3.9 kg,...Ch. 11 - Prob. 37PCECh. 11 - Maximum Overhang Three identical, uniform books of...Ch. 11 - A baseball bat balances 71.1 cm from one end. If a...Ch. 11 - A 2.85-kg bucket is attached to a rope wrapped...Ch. 11 - A child exerts a tangential 53 4-N force on the...Ch. 11 - Predict/Calculate You pull downward with a force...Ch. 11 - One elevator arrangement includes the passenger...Ch. 11 - Atwood's Machine An Atwoods machine consists of...Ch. 11 - A 1.4-kg bicycle tire with a radius of 33 cm...Ch. 11 - Jogger 1 in Figure 11-51 has a mass of 65.3 kg and...Ch. 11 - Predict/Calculate Suppose jogger 3 in Figure 11-51...Ch. 11 - A torque of 0.12 N m is applied to an egg beater...Ch. 11 - A windmill has an initial angular momentum of 8500...Ch. 11 - Two gerbils run in place with a linear speed of...Ch. 11 - Predict/Explain A student rotates on a...Ch. 11 - A puck on a horizontal, frictionless surface is...Ch. 11 - A puck on a horizontal, frictionless surface is...Ch. 11 - As an ice skater begins a spin, his angular speed...Ch. 11 - A disk-shaped merry-go-round of radius 2.63 m and...Ch. 11 - A student sits at rest on a piano stool that can...Ch. 11 - Predict/Calculate A turntable with a moment of...Ch. 11 - A student on a piano stool rotates freely with an...Ch. 11 - Walking on a Merry-Go-Round A child of mass m...Ch. 11 - Predict/Explain Two spheres of equal mass and...Ch. 11 - Turning a doorknob through 0.25 of a revolution...Ch. 11 - A person exerts a tangential force of 36.1 N on...Ch. 11 - To prepare homemade ice cream a crank must be...Ch. 11 - Power of a Dental Drill A popular make of dental...Ch. 11 - For a home repair job you must turn the handle of...Ch. 11 - The L-shaped object in Figure 11-40 consists of...Ch. 11 - The rectangular object in Figure 11-41 consists of...Ch. 11 - Predict/Calculate A circular saw blade accelerates...Ch. 11 - CE A uniform disk stands upright on its edge, and...Ch. 11 - CE Consider the two rotating systems shown in...Ch. 11 - CE Predict/Explain A disk and a hoop (bicycle...Ch. 11 - CE A beetle sits at the nm of a turntable that is...Ch. 11 - After getting a drink of water a hamster jumps...Ch. 11 - A 47.0-kg uniform rod 4.25 m long is attached to a...Ch. 11 - Prob. 75GPCh. 11 - BIO The Masseter Muscle The masseter muscle, the...Ch. 11 - Exercising the Biceps You are designing exercise...Ch. 11 - Prob. 78GPCh. 11 - In Example 11-11, suppose the ladder is uniform,...Ch. 11 - When you arrive at Dukes Dude Ranch you are...Ch. 11 - Prob. 81GPCh. 11 - Flats Versus Heels A woman might wear a pair of...Ch. 11 - BIO A young girl sits at the edge of a dock by the...Ch. 11 - BIO Deltoid Muscle A crossing guard holds a STOP...Ch. 11 - BIO Triceps To determine the force a persons...Ch. 11 - Predict/Calculate Suppose partial melting of the...Ch. 11 - A bicycle wheel of radius R and mass M is at rest...Ch. 11 - A 0.101-kg yo-yo has an outer radius R that is...Ch. 11 - BIO Peak Pedaling Torque The downward force...Ch. 11 - A cylinder of mass m and radius r has a string...Ch. 11 - Bricks in Equilibrium Consider a system of four...Ch. 11 - BIO Correcting Torsiversion Torsiversion is a...Ch. 11 - BIO Correcting Torsiversion Torsiversion is a...Ch. 11 - BIO Correcting Torsiversion Torsiversion is a...Ch. 11 - BIO Correcting Torsiversion Torsiversion is a...Ch. 11 - Referring to Example 11-14 Suppose the mass of the...Ch. 11 - Prob. 97PPCh. 11 - Referring to Quick Example 11-22 Suppose the child...Ch. 11 - Referring to Quick Example 11-22 Suppose...
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