Three rods of copper, brass and steel are welded together to form a Y-shaped structure. The cross-sectional area of each rod is 4cm². The end of copper rod is maintained at 100⁰C and the ends of the brass and steel rods at 80⁰C and 60⁰C, respectively. Assume that there is no loss of heat from the surface of the rods. The length of rods are copper 46cm, brass 13cm and steel 12cm.

 $K\left(Copper\right)=0.92,K\left(steel\right)=0.12,K\left(brass\right)=0.26$ and all values of K are in $cal c{m}^{-1}{s}^{-1}{\left({ }^{0}C\right)}^{-1}$