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Given a Carnot engine with a hot reservoir temperature of 600 K and an efficiency of 45%, find the temperature of the cold reservoir, expressed in degrees Celsius
The coefficient of performance of an ice-making machine is 5 and the power input is 800 W. How much ice can this ice machine theoretically make in one day, starting with water at 30 °C?
The energy efficiency ratio (EER) and coefficient of performance (K) are both used to describe the cooling efficiency of a refrigerator. EER is defined as the ratio of the cooling capacity (in Btu/h) to the electrical power input (in watts). K is defined as the ratio of the heat removal rates (in watts) to the electric power input (in watts). If a refrigerator has K = 6.0, what is its EER?
An industrial chiller unit absorbs 7.5 × 106 J/min of heat from a process and discharges 9.2 × 106 J/min of waste heat to the environment. Calculate the coefficient of performance (COP) of the chiller unit.
A jeweler heats an 8 g gold ring to 500 °C and places it on his workbench to cool down naturally to 30 °C. What is the entropy variation of the gold ring while it cools?
Cryotherapy, a common method for treating athletes' injuries, works by filling a large tub with 100 kg of cold water at 10 °C and pouring in 1 kg of ice at 0 °C. The cold water is being cooled further by ice. i) Is this a reversible or irreversible process, and what is the sign of the entropy variation (ΔS)? Do not use calculations.
During an ice avalanche, 100 kg of ice at 0 °C falls into a large lake. The ice completely melts within a few hours. The lake temperature is assumed to be homogeneous and equal to 10 °C before and after the ice melts. Determine the total entropy change (ΔS) of the ice-water system.
Two identical cylinders, A and B, are connected by a short tube with a valve. Cylinder A contains N molecules of helium, and cylinder B contains 3N molecules of argon. Initially, the valve is closed, and both gases are at the same temperature. After the valve is opened, helium and argon gases expand isothermally. Determine the average number of molecules of helium and argon that will be present in each cylinder.