Stress & strain for steel wire

[kopinator]

A 1.80-m long round steel wire with a cross-sectional diameter of 0.80 mm is placed over a light frictionless pulley, with one end of the wire connected to a 23.0-kg mass and the other end connected to a 14.0-kg mass. By how much does the wire stretch when the masses are in motion? S= F/A
e= ΔL/L°
S= Ye (where Y is Young's modulus for steel= 210 GN/m^2)

I figured the F i needed in the first equation would be the tension in the wire. I got 171N for that answer and then I applied it to S= F/A. I found my S to be about 340163 N/m^2. I don't know whether to use that S for S=Ye or not. Where do I go from here?

 

[cepheid]

I haven't check your numbers, but yes, the tensile stress is the tension force divided by the cross-sectional area, and this is the stress that goes into your equation involving young's modulus.