Windows are often a source of heat loss during the winter. the use of double panes, where there is a gap filled with gas between window panes, can lower heat losses. for a window that is 1 m wide and 2 m tall, calculate the heat loss rate when: a) there is only a glass pane (5 mm thick) with an inside temperature of 15°, an outside temperature of -20°c, and a thermal conductivity of 1.4 w/m/k. b) there is an air gap (10 mm thick) with an inside edge temperature of 10°c, an outside edge temperature of -15°c, and a thermal conductivity of 0.024 w/m/k. be sure to use each step of the problem solving process.

Match the following vocabulary terms to their definitions. 1. amount of energy required to change 1 gram of material from the solid to the liquid state at its melting point 2. a measure of the kinetic energy of the particles of a substance 3. the amount of heat energy required to raise the temperature of 1 gram of liquid water from 14.5°c to 15.5°c 4. amount of energy required to change 1 gram of material from the liquid to the gaseous state at its boiling point 5. the amount of energy required to change 1 gram of a substance 1°c a. temperature b. latent heat of vaporization c. latent heat of fusion d. calorie e. specific heat