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

10th Edition

ISBN:9781337553278

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter12: Static Equilibrium And Elasticity

Section: Chapter Questions

Problem 27AP: The lintel of prestressed reinforced concrete in Figure P12.27 is 1.50 m long. The concrete encloses...

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