Find the final temperature of a cooper rod. Whose area of cross section changes from 10 m^(2) to 11m^(2) due to heating. The copper rod is initially kept at 90K. (Coefficient of superficial expansion is 0.0021/K)

Find the final temperature of a cooper rod. Whose area of cross sectio

1.	Find the final temperature of a cooper rod. Whose area of cross section changes from 10 m^(2) to 11m^(2) due to heating. The copper rod is initially kept at 90K. (Coefficient of superficial expansion is 0.0021/K)
Answer» SOLUTION :Given: Area of copper rod `A_(0)=A_(1)=10 m^(2)` Changes of area CROSS section `DeltaA=A_(2)-A_(1)` `=11-10=1 m^(2)` nitial temperature `t_(1)=90 K` `Delta T=t_(2)-t_(1)` `DeltaT=t_(2)=90` Coefficient of superficial EXPANSION `alpha_(A)=0.0021//K` Then `t_(2)=?` `alpha_(A)=(DeltaA)/(A_(0)Deltat)` `0.0021=(1)/(10xx(t_(2)-90)) rArr t_(2)=90=(1)/(0.0021xx10)` `t_(2)-90=(1)/(0.021)` `t_(2)=(1)/(0.021)+90` `t_(2)=137.6 K`