8. The Achilles tendon, which connects the calf muscles to the heel, is the thickest and strongest tendon in the body. In extreme activities, such as sprinting, it can be subjected to forces. According to one set of experiments, the average area of the Achilles tendon is 80.0 mm², its average length is 30 cm, and its average Young's modulus is 1480 MPa. a) How much tensile stress is required to stretch this muscle by 10.0 % of its length? b) If we model the tendon as a spring, what is its force constant? c) How many times of an 80-kg sprinter weight can be exerted on his Achilles tendon to stretch it by 2.5 cm?

8. The Achilles tendon, which connects the calf muscles to the heel, is the thickest and strongest tendon in the body. In extreme activities, such as sprinting, it can be subjected to forces. According to one set of experiments, the average area of the Achilles tendon is 80.0 mm², its average length is 30 cm, and its average Young's modulus is 1480 MPa. a) How much tensile stress is required to stretch this muscle by 10.0 % of its length? b) If we model the tendon as a spring, what is its force constant? c) How many times of an 80-kg sprinter weight can be exerted on his Achilles tendon to stretch it by 2.5 cm?

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 48PQ: A company is testing a new material made of recycled plastic for use in construction. Figure P14.48...

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Assume Youngs modulus for bone is 1.50 1010 N/m2. The bone breaks if stress greater than 1.50 108 N/m2 is imposed on it. (a) What is the maximum force that can be exerted on the femur bone in the leg if it has a minimum effective diameter of 2.50 cm? (b) If this much force is applied compressively, by how much does the 25.0-cm-long bone shorten?
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