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In a warehouse, a cold room that is maintained at 10oC has a wall made of...

In a warehouse, a cold room that is maintained at 10oC has a wall made of two layers of materials. The inner layer has a thickness of 2 cm and a thermal conductivity of 0.1 W/mK. The outer layer, which is 4 cm thick, has a thermal conductivity of 0.04 W/mK. The temperature of the outside ambient is 30oC . The convective heat transfer coefficients on the outside and the inside of the wall are 40 W/m2K and 20 W/m2K respectively.

  1. Calculate the rate of heat flow through the wall per unit area.
  1. Calculate the temperature of the interface, T interface between the two layers.
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