
When two wires are connected end to end, the tension in them will be same.
Change in length using Hooke's law can be found as,
Y=AΔlFl⇒Δl=AYFl
Total change in length can be written as,
Δl=Δl1+Δl2
⇒Δl=A1Y1Fl1+A2Y2Fl2
⇒F=A1Y1l1+A2Y2l2Δl=π(1.4×10−3)2×2.0×10113.2+π(1.4×10−3)2×1.1×10114.41.4×10−3⇒F=1.54×102=154N