A 6 mm thick sheet of polished 304 stainless steel is suspended in a comparatively large vacuum-drying oven with black walls. The dimensions of the sheet are 30 cm x 30cm, and its specific heat is 565 J/(kg K). If the walls of the oven are uniformly at 150?C and the metal is to be heated from 10 to 120?C, estimate how long the sheet should be left in the oven if(a) Heat transfer by convection may be neglected and(b) The heat transfer coefficient is 3W/(m2 K).GIVENA sheet of polished stainless steel in a large vacuum drying oven with black wallsSheet thickness (s) = 6 mm = 0.006 mSheet dimensions = 30 cm x 30 cm = 0.3 m x 0.3 mSpecific heat of the sheet (c) = 565 J/(kg K)Oven wall temperature (Tw) = 150?C = 423 KSheet temperaturesInitial (Tsi) = 10?C = 283 KFinal (Tsf) = 120?C = 393K

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Oven Tw-423 K T=283 K S-6 mm T-393 K 30 cm 30 cm