Thermodynamics and heat transfer

You may assume that the temperature is uniform through the wall thickness at the end of the winter and again at the end of the summer. You may also assume the density of brickwork is 2000 kg/m3 and the heat capacity of brickwork is C = 0.840 J/g.K.

A wall of a building in a temperate climate can be considered to be a store of heat energy gained during the summer, that can then be released in the winter. The wall measures 3m wide, 2m high and is 300mm in thickness, as shown below. It is constructed of solid brick. The temperature of the wall at the end of the winter is 10°C. During the summer, the wall temperature gradually rises to 20°C. How much heat energy has been stored in the wall?

question 1/2

question 1/2

A sample of insulation material is being tested for its insulation properties. The sample is of dimensions 1.0m x 1.0m, with a thickness of 200mm, as shown in the diagram. The temperature on one side of the insulation is held at 80°C, and on the other side at 20°C. The rate of heat energy that needs to be supplied on the ‘hot’ side to maintain these temperatures is measured to be 6W (6 Watts). What is the thermal conductivity of the insulation material, according to this data?

question 2/2

question 2/2

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https://en.wikipedia.org/wiki/Table_of_specific_heat_capacities)

https://civilsir.com/what-is-the-weight-of-brick-wall-per-sq-ft-and-sq-m/)

Solution 1

Solution 2