Student in Need
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 m2 and its Young's modulus is 1.6×1010 N/m2.
Express your answer to two significant figures and include the appropriate units.
Stress on femur = F/A
Strain = delta L/L = (1/Y)(F/A)
The Attempt at a Solution
F/A = (73 kg * 9.8 m/ss)/(5.2 * 10-4 m2) = 1375769.231 N/m2
deltaL/L = (1/1.6×1010 N/m2)(1375769.231 N/m2) = 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!