Question

Problem 2 - A metallic object is taken out of a very hot furnace with initial temperature of T. (in units of K), total surface area of A, and mass of m kg. This object is suspended in the middle of a large room without contacting any support. Let's assume that heat transfer occurs by radiation only. Since the air around it unlimited, it is reasonable that temperature of the air doe not change and remains at a constant value of Ta (in units of K).Calculate how long it takes until the object cools down to the same temperature as the surrounding air. Just set up the equation that gives the time; you don't need to solve it and find a numerical answer. Conductivity of the metal: k Specific heat of the metal: c Emissivity of the object: e

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