1. Figure 1 shows a simplified diagram of the forces involved in lifting a heavy object of mass L of...

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1. Figure 1 shows a simplified diagram of the forces involved in lifting a heavy object of mass L of 30 kg with the arms.(Figure 1 The diagram shows a simplified view of forces involved in lifting an object. The effort (E) is provided by the extensor muscle attached to the pelvis at approximately 10°to the vertebral column. There is a compressive force (S) on the lumbosacral disc and the weight of the upper body (head, arms and trunk) is represented by Wb.)Assuming that the centre of gravity of the trunk is two-thirds of the way up the spine between the lumbosacral joints and the arms, determine: a) The Compressive force, S, on the lumbosacral disc. b) The angle ?, that the force, S, acts to the column. c) If the force required to rupture the disc is 15,000 N determine the mass (in kg) that can be lifted by the arms without causing damage to the disc.(Assume the total body weight is 700 N).
2, Figure 2 shows a lateral view of a normal spinal column.a) Determine how much compressive stress is present on the L1-L2 intervertebral disc when a person weighing 63 kg stands in anatomical position. Assume that approximately 45 % of body weight is supported by this disc. b) Determine the compressive stress on the L1-L2 intervertebral disc when the individual in a) stands upright holding a 25 kg suitcase.For your calculations, assume that the disc is oriented horizontally and that is has a surface area of 20 cm2.(Figure 2 Lateral view of a normal spinal column. The lumbar spine comprises the 5 vertebraethat are below the thoracic vertebrae and are labelled L1, L2, L3, L4, and L5 in descending orderstarting from the top. The intervertebral discs are numbered as well and are based upon the name of thevertebrae above and below. The first lumbar disc is labelled L1-2, and they are labelled sequentially down toL5-S1.)

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Robert · Accepted Answer

Question 1: 
Solution: 
Part (a) 
The compressive force is, 
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     )  (          )
Part (b) 
      (      (  ))
Part (c) 
  
  
 
    
    

      
 
  

So for 15000 N is,

1. Figure 1 shows a simplified diagram of the forces involved in lifting a heavy object of mass L of 30 kg with the arms.(Figure 1 The diagram shows a simplified view of forces involved in lifting an...

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