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Young's modulus for bone is 1.5x10^10 N/m^2 and that bone will fracture if more than 1.5X10^8 N/m^2 is exerted.

What is the max force that can be exerted on the femur if the effective diameter is 2.5cm?

[tex]Y=F/A[/tex]

[tex]1.50x10^8N/m^2 =\frac{F}{\pi (0.0125m^2)^2}[/tex]

[tex]F=73631N[/tex]

is that correct?

if this force is applied compressively, by how much does the 25cm long bone shorten?

[tex]\Delta L=\frac{FL}{AY}[/tex]

[tex]\Delta L=\frac{73631N*0.25m}{\pi (0.0125m^2)^2 * 1.5x10^{10} N/m^2}[/tex]

[tex]\Delta L=0.0025m[/tex]

I think I did some of this wrong but I'm not sure how to approch these problems. Any guidance?

What is the max force that can be exerted on the femur if the effective diameter is 2.5cm?

[tex]Y=F/A[/tex]

[tex]1.50x10^8N/m^2 =\frac{F}{\pi (0.0125m^2)^2}[/tex]

[tex]F=73631N[/tex]

is that correct?

if this force is applied compressively, by how much does the 25cm long bone shorten?

[tex]\Delta L=\frac{FL}{AY}[/tex]

[tex]\Delta L=\frac{73631N*0.25m}{\pi (0.0125m^2)^2 * 1.5x10^{10} N/m^2}[/tex]

[tex]\Delta L=0.0025m[/tex]

I think I did some of this wrong but I'm not sure how to approch these problems. Any guidance?

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