College Physics (10th Edition)
10th Edition
ISBN: 9780321902788
Author: Hugh D. Young, Philip W. Adams, Raymond Joseph Chastain
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 10, Problem 36P
To determine
The distance between the hip joint and the supporting strap.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
A therapist tells a 70.0 kg patient with a broken leg that he must have his leg in a cast suspended horizontally. For minimum discomfort, the leg should be supported by a vertical strap attached at the center of mass of the leg-cast system. In order to comply with these instructions, the patient consults a table of typical mass distributions and finds that both upper legs (thighs) together typically account for 21.5% of body weight and the center of mass of each thigh is 18.0 cm from the hip joint. The patient also reads that the two lower legs (including the feet) are 14.0% of body weight, with a center of mass 69.0 cm from the hip joint. The cast has a mass of 5.50 kg, and its center of mass is 78.0 from the hip joint. How far from the hip joint should the supporting strap be attached to the cast?
A therapist tells a 74 kg patient with a broken leg that he must have his leg in a cast suspended horizontally. For minimum discomfort, the leg should be supported by a vertical strap attached at the center of mass of the leg–cast system. To comply with these instructions, the patient consults a table of typical mass distributions and finds that both upper legs (thighs) together typically account for 21.5% of body weight and the center of mass of each thigh is 18.0 cm from the hip joint. The patient also reads that the two lower legs (including the feet) are 14.0% of body weight, with a center of mass 69.0 cm from the hip joint. The cast has a mass of 5.50 kg, and its center of mass is 78.0 cm from the hip joint. How far from the hip joint should the supporting strap be attached to the cast?
An individual leans forwards to pick up a box of 100 N. The weight of his upper body has a magnitude of 450 N. The back is pivoting around the base of the vertebral column. Consider the back of the individual as a rigid bar that is controlled by a muscle with an angle of 12° (See picture, d = trunk-head distance = 1 m).a) Calculate the magnitude of muscle force required to lift the box.b) Calculate the magnitude of the force at the base of the vertebral column. Hints: For (a) solve the equilibrium of moments, i.e. what force is required in the muscle to balance out the moments acting around the base of the spine.For (b), solve the equilibrium of forces acting on the spine, including the muscle force you’ve just calculated, in x and y separately. There are two extra forces not shown in the diagram: x and y contact forces acting at the base of the spine. These are whatever is needed to keep the total forces acting on the spine = 0 (so the spine isn’t accelerating off in some…
Chapter 10 Solutions
College Physics (10th Edition)
Ch. 10 - When tightening a bolt, mechanics sometimes extend...Ch. 10 - Prob. 2CQCh. 10 - Two identical uniform 30 cm bricks are placed one...Ch. 10 - (a) If the forces on an object balance, do the...Ch. 10 - (a) Can you change the location of your bodys...Ch. 10 - Serious bicyclists say that if you reduce the...Ch. 10 - Prob. 7CQCh. 10 - In terms of torques, discuss the action of a claw...Ch. 10 - Why is a tapered water glass with a narrow base...Ch. 10 - True or false? In picking an axis about which to...
Ch. 10 - Global warming. As the earths climate continues to...Ch. 10 - If two spinning objects have the same angular...Ch. 10 - You are designing a wheel that must have a fixed...Ch. 10 - Prob. 2MCPCh. 10 - A student is sitting on a frictionless rotating...Ch. 10 - If the torques on an object balance, then it...Ch. 10 - If the forces on an object balance, then it...Ch. 10 - Prob. 6MCPCh. 10 - A person pushes vertically downward with force P...Ch. 10 - String is wrapped around the outer rim of a solid...Ch. 10 - A ball of mass 0.20 kg is whirled in a horizontal...Ch. 10 - A heavy solid disk rotating freely and slowed only...Ch. 10 - A uniform metal meterstick is balanced as shown in...Ch. 10 - Prob. 1PCh. 10 - Calculate the net torque about point O for the two...Ch. 10 - Three forces are applied to a wheel of radius...Ch. 10 - A 4 N and a 10 N force act on an object. The...Ch. 10 - A square metal plate 0.180 m on each side is...Ch. 10 - A cord is wrapped around the rim of a wheel 0.250...Ch. 10 - A certain type of propeller blade can be modeled...Ch. 10 - A 750 g grinding wheel 25.0 cm in diameter is in...Ch. 10 - A grindstone in the shape of a solid disk with...Ch. 10 - A solid, uniform cylinder with mass 8.00 kg and...Ch. 10 - A 2.00 kg stone is tied to a thin, light wire...Ch. 10 - A light rope is wrapped several times around a...Ch. 10 - A thin, light string is wrapped around the rim of...Ch. 10 - 14. A uniform, 8.40-kg, spherical shell 50.0 cm in...Ch. 10 - A hollow spherical shell with mass 2.00 kg rolls...Ch. 10 - A solid disk of radius 8.50 cm and mass 1.25 kg,...Ch. 10 - What is the power output in horsepower of an...Ch. 10 - A solid uniform sphere of mass 5 kg and radius 0.1...Ch. 10 - A playground merry-go-round has a radius of 4.40 m...Ch. 10 - The flywheel of a motor has a mass of 300.0 kg and...Ch. 10 - Calculate the angular momentum and kinetic energy...Ch. 10 - (a) Calculate the magnitude of the angular...Ch. 10 - A small 0.300 kg bird is flying horizontally at...Ch. 10 - A. small 4.0 kg brick is released from rest 2.5 m...Ch. 10 - The London Eye is the tallest Ferris wheel in...Ch. 10 - A certain drawbridge can be modeled as a uniform...Ch. 10 - On an old-fashioned rotating piano stool, a woman...Ch. 10 - The spinning figure skater. The outstretched hands...Ch. 10 - A small block on a frictionless horizontal surface...Ch. 10 - A uniform 2 kg solid disk of radius R 0.4 m is...Ch. 10 - A diver comes off a board with arms straight up...Ch. 10 - A large turntable rotates about a fixed vertical...Ch. 10 - A large wooden turntable in the shape of a flat...Ch. 10 - Which of the objects shown in Figure 10.55 are in...Ch. 10 - (a) In each of the objects in Figure 10.56, what...Ch. 10 - Prob. 36PCh. 10 - Prob. 37PCh. 10 - Prob. 38PCh. 10 - Prob. 39PCh. 10 - Prob. 40PCh. 10 - The horizontal beam in Figure 10.60 weighs 150 N,...Ch. 10 - The boom in Figure 10.61 weighs 2600 N and is...Ch. 10 - A uniform ladder 7.0 m long weighing 450 N rests...Ch. 10 - A 9.0 m uniform beam is hinged to a vertical wall...Ch. 10 - A uniform beam 4.0 m long and weighing 2500 N...Ch. 10 - A diving board 3.00 m long is supported at a point...Ch. 10 - Two people carry a heavy electric motor by placing...Ch. 10 - Pumping iron. A 72.0 kg weightlifter is doing arm...Ch. 10 - The deltoid muscle. The deltoid muscle is the main...Ch. 10 - The rotor (flywheel) of a toy gyroscope has a mass...Ch. 10 - For each of the following rotating objects,...Ch. 10 - Prob. 52GPCh. 10 - A good workout. You are doing exercises on a...Ch. 10 - Prior to being placed in its hole, a 5700 N,...Ch. 10 - Prob. 55GPCh. 10 - One end of a 1.2-m-long beam is hinged to a...Ch. 10 - The farmyard gate. A gate 4.00 m wide and 2.00 m...Ch. 10 - 58. Atwoods machine. Figure 10.72 illustrates an...Ch. 10 - Prob. 59GPCh. 10 - The forces on the foot. A 750 N athlete standing...Ch. 10 - A uniform solid cylinder of mass M is supported on...Ch. 10 - Prob. 62GPCh. 10 - You are trying to raise a bicycle wheel of mass m...Ch. 10 - An experimental bicycle wheel is placed on a test...Ch. 10 - Prob. 65GPCh. 10 - Disks A and B are mounted on shaft SS and may be...Ch. 10 - One end of a thin, uniform rod is connected to a...Ch. 10 - A uniform, 7.5-m-long beam weighing 9000 N is...Ch. 10 - Human moment of inertia. The moment of inertia of...Ch. 10 - While the turntable is being accelerated, the...Ch. 10 - A doubling of the torque produces a greater...Ch. 10 - If the bodys center of mass were not placed on the...Ch. 10 - Torques and tug-of-war. In a study of the...Ch. 10 - If the competitor leans slightly farther back...Ch. 10 - Torques and tug-of-war. In a study of the...
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
- Even when the head is held erect, as in the figure below, its center of mass is not directly over the principal point of support (the atlanto-occipital joint). The muscles at the back of the neck should therefore exert a force to keep the head erect. That is why your head falls forward when you fall asleep in the class. (a) Calculate the force (in N) exerted by these muscles. (Assume w = 48 N, r1 = 4.8 cm, and r2 = 2.9 cm.) magnitude Ndirection ---Select--- upward downward to the left to the right (b) What is the force (in N) exerted by the pivot on the head? magnitude Ndirection ---Select--- upward downward to the left to the rightarrow_forwardThe forearm shown below is positioned at an angle with respect to the upper arm, and a 5.6 kg mass is held in the hand. The total mass of the forearm and hand is 2.1 kg, and their center of mass is 16.1 cm from the elbow. (Assume the biceps muscle exerts a force on the forearm that acts vertically.) 5.6 kg B 37.5 cm 4.0 cm (a) What is the magnitude of the force (in N) that the biceps muscle exerts on the forearm for 0-60%7 N (b) What is the magnitude of the force on the elbow joint (in N) for the same angle? N (c) How do these forces depend on the angle 07 The force that the biceps muscle exerts increases and the force on the elbow joint decreases as increases. They both decrease as @ increases. They both increase as increases. They do not depend on 0. The force that the biceps muscle exerts decreases and the force on the elbow joint increases as increases.arrow_forwardA person bending forward to lift a load "with his back" (Figure a) rather than "with his knees" can be injured by large forces exerted on the muscles and vertebrae. The spine pivots mainly at the fifth lumbar vertebra, with the principal supporting force provided by the erector spinalis muscle in the back. To see the magnitude of the forces involved, and to understand why back problems are common among humans, consider the model shown in Figure b, of a person bending forward to lift a Wo = 195-N object. The spine and upper body are represented as a uniform horizontal rod of weight W₁ = 305 N pivoted at the base of the spine. The erector spinalis muscle, attached at a point two-thirds of the way up the spine, maintains the position of the back. The angle between the spine and this muscle is 12.0⁰. Back muscle R₂ T 12.0° 1T Rx Pivot a Wb Wo ..(a).Find the tension in the back muscle. 1.114 Enter a number. differs from the correct answer by more than 10%. Double check your calculations. kN…arrow_forward
- A person bending forward to lift a load "with his back" (Figure a) rather than "with his knees" can be injured by large forces exerted on the muscles and vertebrae. The spine pivots mainly at the fifth lumbar vertebra, with the principal supporting force provided by the erector spinalis muscle in the back. To see the magnitude of the forces involved, and to understand why back problems are common among humans, consider the model shown in Figure b, of a person bending forward to lift a Wo = 210–N object. The spine and upper body are represented as a uniform horizontal rod of weight Wb = 325 N pivoted at the base of the spine. The erector spinalis muscle, attached at a point two-thirds of the way up the spine, maintains the position of the back. The angle between the spine and this muscle is 12.0arrow_forwardA person bending forward to lift a load "with his back" (Figure a) rather than "with his knees" can be injured by large forces exerted on the muscles and vertebrae. The spine pivots mainly at the fifth lumbar vertebra, with the principal supporting force provided by the erector spinalis muscle in the back. To see the magnitude of the forces involved, and to understand why back problems are common among humans, consider the model shown in Figure b, of a person bending forward to lift a Wo = 210–N object. The spine and upper body are represented as a uniform horizontal rod of weight Wb = 325 N pivoted at the base of the spine. The erector spinalis muscle, attached at a point two-thirds of the way up the spine, maintains the position of the back. The angle between the spine and this muscle is 12.0°. a) find the tension on the back muscle. Answer: ____ kN b) find the compressional force In The spine. Answer: ____ kNarrow_forwardA person bending forward to lift a load "with his back" (Figure a) rather than "with his knees" can be injured by large forces exerted on the muscles and vertebrae. The spine pivots mainly at the fifth lumbar vertebra, with the principal supporting force provided by the erector spinalis muscle in the back. To see the magnitude of the forces involved, and to understand why back problems are common among humans, consider the model shown in Figure b, of a person bending forward to lift a Wo = 215–N object. The spine and upper body are represented as a uniform horizontal rod of weight Wb = 330 N pivoted at the base of the spine. The erector spinalis muscle, attached at a point two-thirds of the way up the spine, maintains the position of the back. The angle between the spine and this muscle is 12.0°. (a) Find the tension in the back muscle. (b) Find the compressional force in the spine. (Enter the magnitude.)arrow_forward
- A person bending forward to lift a load "with his back" (Figure a) rather than "with his knees" can be injured by large forces exerted on the muscles and vertebrae. The spine pivots mainly at the fifth lumbar vertebra, with the principal supporting force provided by the erector spinalis muscle in the back. To see the magnitude of the forces involved, and to understand why back problems are common among humans, consider the model shown in Figure b, of a person bending forward to lift a Wo = 195–N object. The spine and upper body are represented as a uniform horizontal rod of weight Wb = 290 N pivoted at the base of the spine. The erector spinalis muscle, attached at a point two-thirds of the way up the spine, maintains the position of the back. The angle between the spine and this muscle is 12.0°. In figure (a), a man bends his back forward to lift a set of weights. The hips are labeled as the pivot and the back muscle is also labeled to the right of the pivot. In figure (b), a…arrow_forwardA person bending forward to lift a load "with his back" (Figure a) rather than "with his knees" can be injured by large forces exerted on the muscles and vertebrae. The spine pivots mainly at the fifth lumbar vertebra, with the principal supporting force provided by the erector spinalis muscle in the back. To see the magnitude of the forces involved, and to understand why back problems are common among humans, consider the model shown in Figure b, of a person bending forward to lift a W. 195-N object. The spine and upper %3D body are represented as a uniform horizontal rod of weight W, = 335 N pivoted at the base of the spine. The erector spinalis muscle, attached at a point two-thirds of the way up the spine, maintains the position of the back. The angle between the spine and this muscle is 12.0°. Back muscle R, T 12.0° Pivot R W. Wh (a) Find the tension in the back muscle. kN (b) Find the compressional force in the spine. (Enter the magnitude.) kNarrow_forwardA person bending forward to lift a load "with his back" (Figure a) rather than "with his knees" can be injured by large forces exerted on the muscles and vertebrae. The spine pivots mainly at the fifth lumbar vertebra, with the principal supporting force provided by the erector spinalis muscle in the back. To see the magnitude of the forces involved, and to understand why back problems are common among humans, consider the model shown in Figure b, of a person bending forward to lift a W 170-N object. The spine and upper body are represented as a uniform horizontal rod of weight W = 355 N pivoted at the base of the spine. The erector spinalis muscle, attached at a point two-thirds of the way up the spine, maintains the position of the back. The angle between the spine and this muscle is 12.0°. Back muscle Pivot = a R₂ T 12.0° Rx Wb Wo (i) (a) Find the tension in the back muscle. 1.114 Your response differs from the correct answer by more than 10%. Double check your calculations. kN (b)…arrow_forward
- A person bending forward to lift a load "with his back" (Figure a) rather than "with his knees" can be injured by large forces exerted on the muscles and vertebrae. The spine pivots mainly at the fifth lumbar vertebra, with the principal supporting force provided by the erector spinalis muscle in the back. To see the magnitude of the forces involved, and to understand why back problems are common among humans, consider the model shown in Figure b, of a person bending forward to lift a Wo = 195–N object. The spine and upper body are represented as a uniform horizontal rod of weight Wb = 290 N pivoted at the base of the spine. The erector spinalis muscle, attached at a point two-thirds of the way up the spine, maintains the position of the back. The angle between the spine and this muscle is 12.0°. In figure (a), a man bends his back forward to lift a set of weights. The hips are labeled as the pivot and the back muscle is also labeled to the right of the pivot. In figure (b), a…arrow_forwardThe figure shows the finishing position of a body builder's arm who is performing a standing lateral raise with a 5.00-kg dumbbell. This is an excellent exercise that isolates the lateral deltoid muscle. The weight of the arm itself is 42.5 N, and it acts at point A in the figure. Given the information shown, and the fact that 0 = 9.74°, (a) find the magnitude of the tension force in the deltoid (Fa) and (b) the (Fa) and (b) the normal force from the shoulder joint (F.) acting on the humerus bone that holds the arm in this equilibrium position. (a) Number (b) Number i 0.075 m 12 0 0 Units Units F. 0.250 m W₁ 0.510 m < arm 5 kg Waarrow_forwardAssume a person bends forward to lift a load "with his back" as shown in Figure (a). The spine pivots mainly at the fifth lumbar vertebra, with the principal supporting force provided by the erector spinalis muscle in the back. To see the magnitude of the forces involved, consider the model shown in Figure (b) for a person bending forward to lift a W, = 205-N object. The spine and upper body are represented as a uniform horizontal rod of weight W, = 320 N, pivoted at the base of the spine. The erector spinalis muscle, attached at a point two-thirds of the way up the spine, maintains the position of the back. The angle between the spine and this muscle is 0 = 10.5°. Back muscle R, Pivot R W2 a (a) Find the tension T in the back muscle. N (b) Find the compressional force in the spine. (c) Is this method a good way to lift a load? O Yes No Explain your answer, using the results of parts, using the results of parts (a) and (b). This answer has not been graded yet. (d) Can you suggest a…arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
Principles of Physics: A Calculus-Based Text
Physics
ISBN:9781133104261
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning