A black sphere (2.5 cm diam) is placed in a large infrared heating oven whose walls are maintained at 370?C. The temperature of the air in the oven is 90?C and the heattransfer coefficient for convection between the surface of the sphere and the air is 30 W/(m2 K). Estimate the net rate of heat flow to the sphere when its surface temperature is 35?C.GIVENA black sphere in a large infrared heating ovenSphere diameter (D) = 2.5 cm = 0.025 mOven wall temperature (T2) = 370?C = 643 KOven air temperature (T??) = 90?C = 363 KConvective heat transfer coefficient (hc) = 30 W/(m2 K)Sphere surface temperature (T1) = 35?C = 308 KASSUMPTIONSThe oven walls arediffuse

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Oven A2 T-= 363 K T2= 643 K T- 308 K D-0.025 m