You are trying to reduce the heat transfer rate from a furnace. Currently, the outer surface...

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You are trying to reduce the heat transfer rate from a furnace. Currently, the outer surface of the furnace has an emissivity of 1 = 0.8, which radiates to the surroundings with an average emissivity of 2 = 0.9 For each of the following situations, determine the ratio of new and old heat transfer rates (new) Q old). You coat the surface of the furnace with a more reflective material. Now, 1 = 0.2, while 2 = 0.9 Determine the ratio of new and old heat transfer rates ( _ new' old). a) = 018 Qnew old Q = 0 27 b) new Q c) Q new new Q Q Q old old old = 059 = 0 85 You are trying to reduce the heat transfer rate from a furnace. Currently, the outer surface of the furnace has an emissivity of 1 = 0.8, which radiates to the surroundings with an average emissivity of 2 = 0.9 For each of the following situations, determine the ratio of new and old heat transfer rates (new) Q old). You coat the surface of the furnace with a more reflective material. Now, 1 = 0.2, while 2 = 0.9 Determine the ratio of new and old heat transfer rates ( _ new' old). a) = 018 Qnew old Q = 0 27 b) new Q c) Q new new Q Q Q old old old = 059 = 0 85