A composite wire of uniform diameter 3.0 mm consisting of a copper wire of length 2.2m and a steel wire of length 1.6m stretches under a load by 0.7 mm. Calculate the load, given that the Young's modulus for copper is `1.1 xx 10^(11) Pa` and for steel is `2.0 xx 10^(11)Pa`.

Explanation

The extension `DeltaL_("copper")=(Fl_(1))/(AY_(c))`
`=(Fxx2.2)/(pi(0.003)^(2)xx1.1xx10^(11))`
and `DeltaL_("steel")=(Fl_(2))/(AY_(s))`
`=(Fxx1.6)/(pi(0.003)^(2)xx2xx10^(11))`
Given `DeltaL_("copper")+DeltaL_("steel")=0.7xx10^(-3)`
After simplifying above equations we get
`F=176.8N`