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 principalsupporting 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 personbending 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 theway up the spine, maintains the position of the back. The angle between the spine and this muscle is 12.0⁰.Back muscleR₂T 12.0°1TRxPivotaWbWo..(a).Find the tension in the back muscle.1.114Enter a number. differs from the correct answer by more than 10%. Double check your calculations. kN(b) Find the compressional force in the spine. (Enter the magnitude.)1.09Your response differs from the correct answer by more than 10%. Double check your calculations. kN

Answered: Image /qna-images/answer/8205b14e-188e-44fb-8abb-e41ba8f662e2.jpg

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 W. 195-N object. The spine and upper body are represented as a uniform horizontal rod of weight W=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 Pivot R R₂ b T 12.0° W₂ W₂ ↑ (a).Find the tension in the back muscle. 1.114 x Enter a number. differs from the correct answer by more than 10%. Double check your calculations. kN (b) Find the compressional force in the spine. (Enter the magnitude.) 1.09 X Your response differs from the correct answer by more than 10%. Double check calculations, KN

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 W. 195-N object. The spine and upper body are represented as a uniform horizontal rod of weight W=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 Pivot R R₂ b T 12.0° W₂ W₂ ↑ (a).Find the tension in the back muscle. 1.114 x Enter a number. differs from the correct answer by more than 10%. Double check your calculations. kN (b) Find the compressional force in the spine. (Enter the magnitude.) 1.09 X Your response differs from the correct answer by more than 10%. Double check calculations, KN

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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