How Much Force Can a Human Femur Withstand Before Fracturing?

AI Thread Summary
The discussion focuses on calculating the maximum force a human femur can withstand before fracturing, given Young's Modulus and the fracture stress threshold. The user initially struggles with applying the formulas due to a lack of specific lengths for the calculations. They inquire about the correct approach to use the provided equations effectively. Ultimately, the user resolves their confusion independently. The thread highlights the importance of understanding tensile stress and strain in relation to bone mechanics.
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Homework Statement



Assume that Young's Modulus for bone is 1.50 X 10^10 N/m2 and that the bone will fracture if more than 1.50 X 10^8 N/m2 is exerted.

(a) What is the maximum force that can be exerted on the femur bone in the leg if it has a minimum effective diameter of 2.60 cm?

(b) If a force of this magnitude is applied compressively, by how much does the 24.0 cm long bone shorten?

Homework Equations



Y = tensile stress / tensile strain

tensile stress = F/A
tensile strain = delta L / Initial L

The Attempt at a Solution



I understand the concept, but i can't figure out where to plug the numbers into. Since I don't have any lengths for part a, I guess you wouldn't use the entire young's equation, but what exactly would I use?

Any help would be great! Thanks!
 
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never mind, I figured it out
 
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