Kelvin-Planck and Clausius statements of the second law of thermodynamics are ve
ID: 1842124 • Letter: K
Question
Kelvin-Planck and Clausius statements of the second law of thermodynamics are very useful in the understanding of heat engine operation. State both of them. By using 2 kW of electrical power, a heat engine creates a heating effect of 30 000 kJ/h for a space maintained at 288 K. Determine the minimum source temperature, and state your assumption. A sink and source temperatures for a Carnot heat engine are given by T_L and T_H respectively. If this engine's thermal efficiency is desired to be doubled, what is the new temperature of the source? Assume that the temperature of the sink is held constant. The manufacturer of a washing machine claims that the washer will use RM155/year worth of hot water, provided that the water is heated by a gas water heater at a natural gas rate, which is RM5.61/therm (1 therm = 105 500 kJ). Calculate total energy transfer to water per week, if the efficiency of the gas water heater is 61 %.Explanation / Answer
a) Kelvin Plank Statement
It is impossible for any device that operates on cycle to receive heat from a single reservoir and produce net amount of work
or
No engine have efficiency of 100 percent
It is used for heat engine
Clausius Statement
It is impossible to construct a device that operates in cycle and produces no effect other that the transfer of heat from lower-temperature body to higher temperature
It is relateto to heat pump and referigerator
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.