(a) What is the heat flow through a glass window of dimensions 0.50 m x 0.50 m and thickness 4.0 mm, when the inside temperature is 25 celsius and the outside temperature is -15 celsius. (thermal conductivity of glass is 0.8 W/mK and of air is 0.024 W/mK)
(b) What is the heat flow when a thicker glass window of 8.0 mm is used?
(c) Estimate the heat flow when a double pane of glass is used with a 4.0 mm air gap between the panes? Each individual glass sheet is 4.0 mm thick.