Question

1. [1pt]
The elastic energy stored in your tendons can contribute up to 35% of your energy need when running. During a race, sprinters will use shoes with nearly no padding because their body returns more energy without it. Find the energy stored in an athlete's quadriceps tendon with length 46.0 mm and diameter 7.00 mm when the tendon is strained by 11%. The Young's modulus of the tendon is 252 MPa.

Answer 1

Given is:-

Strain = 11% = 0.11

Young's modulus =  

Diameter d = 7 mm or

Thus the area of cross section of tendon will be

Length of the tenson = 46 mm or 0.046m

therefore the volume of the tendon will be

by plugging all the values we get

or

which gives us

Now,

The energy stored is given as

by plugging all the values we get

which gives us