Chapter 5, Problem 5.20CU

A reversible power cycle whose thermal efficiency is 50% operates between a reservoir at 1800 K and a reservoir at a lower temperature T. Determine T, in K.

An air conditioner operating at steady state maintains a dwelling at 20 C on a day when the outside temperature is 35 C. Energy is removed by heat transfer from the dwelling at a rate of 2800 J/s while the air conditioner's power input is 0.8 kw. (a) Determine the coefficient of performance of the air conditioner. (b) Determine the power input required if it was a Carnot refrigerator. English (United States) 目 98%

Kelvin-Planck statement defines the Second law of thermodynamics as a. It is impossible to construct a machine that will operate in a cycle, extract heat from a reservoir, and do an equivalent amount of work on the surroundings. b. It is impossible to construct a device that operates in a cycle and produces no effect other than the transfer of heat from a lower-temperature body to a higher-temperature body. c. It is possible to construct a device that operates in a cycle and produces no effect other than the transfer of heat from a lower-temperature body to a higher-temperature body. d. It is possible to construct a machine that will operate in a cycle, extract heat from a reservoir, and do an equivalent amount of work on the surroundings.