Consider a slab of thickness $L=25mm.$ One surface is

kept at $100C$ and the other surface at $0C.$ Determine

a$)$ the heat flux across this slab if it is made of pure

copper $(k=22\mathrm{.}7\frac{W}{m}.K)$

b$)$ value of temperature at $x=12\mathrm{.}5mm$