Thermal expansion and conductivity

Problem:

A mercury thermometer has a bulb of volume 0.100 cm3 at 10°C.  The capillary tube above the bulb has a cross-sectional area of 0.012 mm2.  The volume thermal expansion coefficient of mercury is 1.8*10-4 (°C)-1.  How much will the mercury rise when the temperature rises by 20°C?

Solution:

Problem:

A bar of gold is in thermal contact with a bar of silver of the same length and area.  One end of the compound bar is maintained at 80 oC and the opposite end is at 30 oC.  When the heat flow reaches steady state, find the temperature at the junction.
The thermal conductivity of gold is 314 W/(moC), and the thermal conductivity of silver is 427 W/(moC).

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Solution:

Problem:

A Thermopane window of area 6 m2 is constructed of two layers of glass, each 4 mm thick, separated by an air space of 5 mm.  If the inside is at 20 oC and the outside is at -30 oC, what is the rate of heat loss through the window?
Thermal conductivity of Thermopane: 0.8 W/(moC)
Thermal conductivity of air: 0.0234 W/(moC)

Solution: