ANsume a person benis Torward to lift a load "with s buk as shown in Figure P12.48a. The spine pivota iuly at the fifth lumbar vertebra, with the princinal pporting force provided by the erector spinalis muscle in the back. To see the magnitude of the forces involved. consider the model shown in Figure P12.48b for a per- son bending forward to lift a 200-N object. The spine and upper body are represented as a uniform horizontal rod of weight 350 N. pivoted at the base of the spine. The erec tor spinalis muscle, attached at a point two-thirds of the way up the spine, maintains the position ofthe back.The Back muscle R, Pivot T 12.0 200 N 350 N Figure P12.48 angle between the spine and this musele is 0 == 12.0°. Find (a) the tension T'in the back muscle and (b) the compres- sjonal force in the spine. -

ANsume a person benis Torward to lift a load "with s buk as shown in Figure P12.48a. The spine pivota iuly at the fifth lumbar vertebra, with the princinal pporting force provided by the erector spinalis muscle in the back. To see the magnitude of the forces involved. consider the model shown in Figure P12.48b for a per- son bending forward to lift a 200-N object. The spine and upper body are represented as a uniform horizontal rod of weight 350 N. pivoted at the base of the spine. The erec tor spinalis muscle, attached at a point two-thirds of the way up the spine, maintains the position ofthe back.The Back muscle R, Pivot T 12.0 200 N 350 N Figure P12.48 angle between the spine and this musele is 0 == 12.0°. Find (a) the tension T'in the back muscle and (b) the compres- sjonal force in the spine. -

Name: angle between the spine and this muscle is 0 == 12,0°, Find(a) the te
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Description: angle between the spine and this muscle is 0 == 12,0°, Find(a) the tension T'in the back muscle and (b) the compres-Assume a person bends forward to lift a load "withbyk- as sliown in Figure P12.48a. The spine pivotamaiuly at the fifth lumbar verteb

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter14: Static Equilibrium, Elasticity, And Fracture

Section: Chapter Questions

Problem 38PQ: At a museum, a 1300-kg model aircraft is hung from a lightweight beam of length 12.0 m that is free...

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