A flat plate has thickness 5 cm, thermal conductivity 1 W/mk, convective heat transfer coefficient on its two flat faces are 10 W/m2k and 20 W/m2. The overall heat transfer coefficient for the plate...

A flat plate has thickness 5 cm, thermal conductivity 1 W/mk, convective heat transfer coefficient on its two flat faces are 10 W/m2k and 20 W/m2. The overall heat transfer coefficient for the plate is—

(a) 5 W/m2K                       (b) 6.33 W/m2K

(c) 20 W/m2K                     (d) 30 W/m2K