×
Get Full Access to Physics - Textbook Survival Guide
Get Full Access to Physics - Textbook Survival Guide
×

# BIO Tendon-Stretching Exercises. As part of an exercise

ISBN: 9780321675460 31

## Solution for problem 63P Chapter 11

University Physics | 13th Edition

• Textbook Solutions
• 2901 Step-by-step solutions solved by professors and subject experts
• Get 24/7 help from StudySoup virtual teaching assistants

University Physics | 13th Edition

4 5 0 257 Reviews
13
2
Problem 63P

BIO Tendon-Stretching Exercises. As part of an exercise program, a 75-kg person does toe raises in which he raises his entire body weight on the ball of one foot (?Fig. P11.59?). The Achilles tendon pulls straight upward on the heel bone of his foot. This tendon is 25 cm long and has a cross-sectional area of 78 mm2 and a Young’s modulus of 1470 MPa. (a) Draw a free-body diagram of the person’s foot (everything below the ankle joint). Ignore the weight of the foot. (b) What force does the Achilles tendon exert on the heel during this exercise? Express your answer in newtons and in multiples of his weight. (c) By how many millimeters does the exercise stretch his Achilles tendon?

Step-by-Step Solution:

Solution Step 1 of 3: (a) Draw a free-body diagram of the person’s foot (everything below the ankle joint). Ignore the weight of the foot. A m= 75 kg person has his tendon l=25 cm=0.25m long and cross sectional area A=78 mm =78× 10 6 m having young’s modulus of Y=1470 MPa=1470 × 10 Pa. Here in 6 part (a) we need to write the free body diagram for the ankle when the person raises his entire body weight on the ball of one foot. The free body diagram for the ankle is, Step 2 of 3: (b) What force does the Achilles tendon exert on the heel during this exercise Express your answer in newtons and in multiples of his weight. In order to calculate the force exerted by the achilles tendon on the heel during the exercise , we need to use the definition of torque That is, F × d = mgh From the given figure d= 4.6 cm and h =12.5 cm F(4.6 cm ) = mg(12.5 cm) F=2.72 mg 2 Substituting m= 75 kg and g=9.8 m/s 2 F = 2.72 (75 kg)(9.8 m/s ) F= 2000 N Therefore, the force exerted on the heel is F= 2000 N = 2.72 mg.

Step 3 of 3

##### ISBN: 9780321675460

The answer to “BIO Tendon-Stretching Exercises. As part of an exercise program, a 75-kg person does toe raises in which he raises his entire body weight on the ball of one foot (?Fig. P11.59?). The Achilles tendon pulls straight upward on the heel bone of his foot. This tendon is 25 cm long and has a cross-sectional area of 78 mm2 and a Young’s modulus of 1470 MPa. (a) Draw a free-body diagram of the person’s foot (everything below the ankle joint). Ignore the weight of the foot. (b) What force does the Achilles tendon exert on the heel during this exercise? Express your answer in newtons and in multiples of his weight. (c) By how many millimeters does the exercise stretch his Achilles tendon?” is broken down into a number of easy to follow steps, and 122 words. University Physics was written by and is associated to the ISBN: 9780321675460. The full step-by-step solution to problem: 63P from chapter: 11 was answered by , our top Physics solution expert on 05/06/17, 06:07PM. Since the solution to 63P from 11 chapter was answered, more than 582 students have viewed the full step-by-step answer. This textbook survival guide was created for the textbook: University Physics, edition: 13. This full solution covers the following key subjects: tendon, foot, Achilles, weight, exercise. This expansive textbook survival guide covers 26 chapters, and 2929 solutions.

#### Related chapters

Unlock Textbook Solution

Enter your email below to unlock your verified solution to:

BIO Tendon-Stretching Exercises. As part of an exercise

×
Get Full Access to Physics - Textbook Survival Guide