The femur is a bone in the leg whose minimum cross-sectional area is about 3.60 10-4 m2. A compressional force in excess of 6.90 104 N will fracture this bone.

(a) Find the maximum stress that this bone can withstand.

(b) What is the strain that exists under a maximum-stress condition

i tried to solve for part a and i got 1.92 and it was worng using thre equation force divided by area plaease help me. what would the right answer be

3 answers

Your formula is correct, but you forgot to take care of the exponents (10^4=10000, etc.)

Someone has asked the same question, and the response is here.
http://www.jiskha.com/display.cgi?id=1289886124
i tried to answer part b but not 100 percent sure what the young modulus is for bone i know part a is 1.92E8. please help how to solve part b
If you read the article given in the link, you will realize that Young's modulus for bone is variable, depending on many factors, one of which is bone density.

Such information for a physics question would normally be supplied, but for completeness, the answer to part b had been completed, using an average value of 20 GPa.