[QUE/TH-02006] TH-PROBLEM

A metal wire of cross-sectional area 0.0085 cm$^2$ under a
tension of 20 N and a temperature of 20$^\circ$C is stretched
between two rigid supports 1.2 m apart. If the temperature is
reduced to 8$^\circ$C, what is the final tension? (Assume that
$\alpha$ and $Y$ remain constant at the values
$1.5\times10^{-5}$K$^{-1}$ and $2.0\times10^9$ N/m$^2$ respectively)