Question

A thermopane window consists of two glass panes, each 0.50 cm thick, with a 1.0-cm-thick sealed layer of air in between. (Use 0.8 J/s middot m middot degree C for the thermal conductivity of glass and 0.0234 J/s middot m middot degree C for the thermal conductivity of air to answer the following.) (a) If the inside surface temperature is 22.9 degree C and the outside surface temperature is 0.0 degree C, determine the rate of energy transfer through 1.60 m^2 of the window. (b) Compare your answer to (a) with the rate of energy transfer through 1.60 m^2 of a single 1.0-cm-thick pane of glass. Disregard surface air layers. W

Answer 1

The expression for heat conduction through a solidis Here, kis the coefficient of therm al conductivity of glass window, A is cross-sectional area and△T is the temperature differnce and Δι is the thickness For a double window ane k|k 2x0.5x102m 0.8J/s.m.C 1.0x102 m 0.02341/sm"C -0.4398 s.mC Rate of heat conduction can be cal culated by using equati on (1) 22.9"C At 0.4398 s.m2C 83.3W