ME 410-2 Name:_______________________________ Homework #2 (due September 3, 2010) Homework Format1. Use this page as a cover sheet. 2. One problem per page. 3. Always state what is given, your assumptions, provide a sketch, and analysis. Circle your answer. Include units. 4. Write legibly. 5. No late homework accepted. 6. Work independently. 7. Use paper with four straight edges. 8. Staple together your work. 1.During a cold winter, the surface of a lake develops a layer of ice of unknown thickness L. Known are the lake water temperature Tw= 4ºC, the atmospheric air temperature Ta= -30ºC, and the temperature of the underside of the ice layer T0= 0ºC. The thermal conductivity of ice is k= 2.10 W/m⋅K. The convective heat transfer coefficients on the water and air sides of the ice layer are hw=375 W/m2⋅K and ha= 65 W/m2⋅K, respectively. Calculate the temperature of the upper surface of the ice layer, Ts, and the ice thickness, L. 2.Under certain environmental conditions, the temperature of the human skin (30ºC) is lower than the core
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