Physics (5th Edition)
5th Edition
ISBN: 9780321976444
Author: James S. Walker
Publisher: PEARSON
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Chapter 11, Problem 77GP
Exercising the Biceps You are designing exercise equipment to operate as shown in Figure 11-58 where a person pulls upward on an elastic cord. The cord behaves like an ideal spring and has an unstretched length of 31 cm. If you would like the torque about the elbow joint to be 81 N · m in the position shown what force constant, k, is required for the cord?
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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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