Problem 8 In a non-flow process carried out on 5.4 kg of a substance, there was a specific internal energy decrease of 50 kJ/kg and a work transfer from the substance of 85 kJ/kg. Determine the heat transfer and state whether it is gain or loss.

4) A ground source heat pump heats a building by extracting heat from the ground and pumping it into the building. Define: Qc = heat extracted from the ground, Qn= heat pumped into the building, W = electric energy used by the heat pump, Tc= temperature of the ground, T = temperature of building (Qc, Qn, and W are positive by definition). Assume Tr > Tc. a) Draw a diagram showing energy flow in and out of the heat pump. b) Write a general expression for the change AS in the entropy of the "universe", that is the heat pump plus the cold and hot reservoirs, in terms of the quantities defined above. Now assume ideal (reversible) operation, and take Te= 10 °C and Tp= 20 °C. What is the coefficient of performance (ČOP) of the heat pump? By what factor would this change if we had Tc = 0 °C instead?

QUESTION 9 During the video on heat conduction, H through a single pane window was calculated. Now, consider a window that has wo panes with a 6 mm air gap between them. Each pane has an area of 1.9 m. The window separates the inside of a house at 22 °C from the outside at 0°C. Let Kair = 0.03 W/(m-K). Hint: This problem can be simplified by noting that the thermal conductivity of glass is much greater than air, so the effect of the glass on the total conductivity can be ignored. Therefore, the purpose of the two glass panes is to support the layer of air between them. Calculate the heat current H through the double glass pane window in watts. Do not include units in your answer and state your numerical answer in normal form. QUESTION 10 Consider process 3 in the figure below (or in First_Exam_Figures.pdf) shown by the bold solid line with an arrowhead. The pressure of a gas is decreased at constant volume. V. Click Save and Submit to save and submit. Click Save All Ansuers to save all…

Two bodies P and Q are in thermal equilibrium. This statement means that 18. A There is no transfer of energy between P and Q. B The rate of transfer of heat between P and Q is constant. C P and Q have the same amount of internal energy. D Pand Q are in physical contact with cach other.