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**1. Homework Statement**

By what amount does the 52-cm-long femur of an 73 kg runner compress at this moment? The cross-section area of the bone of the femur can be taken as 5.2×10

^{-4}m

^{2}and its Young's modulus is 1.6×10

^{10}N/m

^{2}.

Express your answer to two significant figures and include the appropriate units.

**2. Homework Equations**

Stress on femur = F/A

Strain = delta L/L = (1/Y)(F/A)

**3. The Attempt at a Solution**

F/A = (73 kg * 9.8 m/s

^{s})/(5.2 * 10

^{-4}m

^{2}) = 1375769.231 N/m

^{2}

deltaL/L = (1/1.6×10

^{10}N/m

^{2})(1375769.231 N/m

^{2}) = 8.598557692 * 10

^{-5}

(8.598557692 * 10

^{-5}) * 0.52 m = 4.47125 * 10

^{-5}m = 4.5 * 10

^{-5}m

I'm not sure what I'm doing wrong; any help would be appreciated!

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