This doesn't seem particularly hard, thought it was simply an F/A situation but apparently not. A fiber with a diameter of 25 micro meters is subjected to elongation load of 25 g along the fiber axis. What is the stress on the fiber? Is the applied stress a shear or a tensiles stress. I said it was a tensil stress and went on to compute F/A. F was .025Kg * 9.8N and A was simply ((25*10^-6)/2)^2*pi. The resultant stress was 500 MPa. The correct answer is .125 MPa. Any suggestions??!