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A plastic coating is applied to wood panels by first depositing molten polymer on a panel and then cooling the surface of the polymer by subjecting it to airflow at 25C. As first approximations, the heat of reaction associated with solidification of the polymer may be neglected and the polymer/wood interface may be assumed to be adiabatic. If thickness of the coating is L=1.5mm and it has an initial uniform temperature of Ti=180C, (i) how long will it take for the surface to achieve a safe-to-touch temperature of 45C if the convection coefficient is uniform and is h=180W/(m2K) ? (ii) What is the corresponding value of the interface temperature? The thermal conductivity and diffusivity of the plastic are k=0.2W/(m.K) and =1107m2/s, respectively. Hint: sketch temperature profile for any time t in plastic coating, and consider the boundary condition at the interface