How Much Force Can a Human Femur Withstand Before Fracturing?

[yb1013]

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!

 

[yb1013]

never mind, I figured it out