A Cook leaves a plastic spoon and a wooden spoon in a pot of hot water for the same length of time , the spoon have the same mass if plastic has a higher specific heat capacity than wood , which spoon will have a larger change in temperature ? Explain why .

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?

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A 100 g rock at 30°C is completely immersed in970 g of water at 50°C. Which one of the following statements is true right after the rock goes in?     a. It depends on the specific heat of the rock. b. The rock gives the water thermal energy and gets no thermal energy in return. c. The rock and the water give each other thermal energy, but the rock gives more than it gets. d. The rock and the water give each other thermal energy, but the water gives more than it gets.

SKIN temperatures (57 C)the iatent neat or vap moi water ny of watch p=998.2 kg/m'. 3. Assume that the thickness of the tissue between the interior and the exterior of the body is d =3 cm and that the average area through which conduction can occur is A =1.5 m². Find heat transferred by conduction per hour if temperature difference between the inner body and the skin is AT = 2°C. Coefficient of thermal for tissue without blood is K. = 18 × 10-2 Cal /m-hr-ºC.

0.4 kg water is at room temperature 23 degrees in an aluminum container. An unknown metal with 0.5 kg mass is placed inside the water raising its temperature to 40 degrees. A)What is the specific heat of the unknown metal. B) Would the equilibrium temperature greater, less or the same if the system was not properly isolated.