A completely reversible air conditioner provides 36,000 Btu/h of cooling for a space maintained at 70°F while rejecting heat to the environmental air at 110°F. Calculate the rate at which the entropies of the two reservoirs change and verify that this air conditioner satisfies the increase of entropy principle.

Q: Refrigerant-134a at 140 kPa and –10°C is compressed by an adiabatic 0.5-kW compressor to an exit…

A: Given Data: Refrigerant type: R-134a The temperature of refrigerant at the entry of compressor is T1…

Q: A reversible Carnot engine operates between 27°C and 1527°C, and produces 400 kW of net power. The…

A: Given, Temperature at which heat is added = T1 = 1527 oC = 1800 K Temperature at which heat is…

Q: 3. Air enters a nozzle with an inlet velocity of 10 m/s and a temperature of 365 K, and the nozzle…

A: T1=365 KV1=10 msecP2= 1barγ=1.4 R=.287 kjkgKNow apply SFEE equation for nozzleh1+v122000=h2+v222000…

Q: Refrigerant-134a at 140 kPa and 210C is compressed by an adiabatic 1.3-kW compressor to an exit…

A: In this problem, the initial temperature is greater than the final temperature so it is not…

Q: Devices can be combined to perform a variety of tasks. An adiabatic compressor, with air as the…

A: To find: The magnitude of power delivered to generator by turbine. Given: The temperature of the…

Q: For a refrigeration cycle using refrigerant 134a and a compressor isentropic efficiency of 80% and a…

A: R134a refrigerant is givenCP,R134a=0.85 kJ/kg.Kisentropic efficiency of compressor, ηc=80%mass flow…

Q: Devices can be combined to perform a variety of tasks. An adiabatic compressor, with air as the…

A: To find: The magnitude of power delivered to generator by turbine. Given: The temperature of the…

Q: Steam at 3 Mpa and 450 oC is expanded to 40 kPa in an adiabatic turbine with an isentropic…

A:

Q: Does a cycle for which ∮ δQ > 0 violate the Clausius inequality? Why?

A: Yes, the ∮ δQ > 0 violate the Clausius law of inequality because the Clausius law of Inequality…

Q: Steam enters a turbine steadily at 3 MPa and 450°C at a rate of 8 kg/s and exits at 0.2 MPa and…

A: Determine enthalpy and entropy at inlet and exit conditions using steam table

Q: Problem-1: Water steam flows steadily through an adiabatic turbine. The inlet condition steam are 4…

A:

Q: Air enters an adiabatic nozzle at 250 kPa and 700 K with a very low velocity and exits at 500 m/s.…

A: Given data as per question The pressure of air at entry=250 kpa The temperature of the air at…

Q: Steam enters an adiabatic turbine steadily at 4 MPa and 500°C at a rate of 6 kg/s and exits at 0.3…

A:

Q: Refrigerant 134-a enters the coil of the condenser of a residential heat pump at 500kPa and 400C and…

A: The superheated refrigerant enters the compressor and leave as a saturated liquid. Therefore,…

Q: Superheated steam enters the turbine of a steam power plant at 5 MPa and 450 ºC, and exits at 10…

A: Given:P1=5 MPaT1=450°CP2=10 KPaη=90%m=10 Kg/s

Q: Steam enters an adiabatic turbine at P1 MPa and T1°C with a mass flow rate of z kg/s and leaves at…

A:

Q: Plot the Carnot cycle on a P-V diagram. With thermodynamic temperature scale Prove that the absolute…

A: P-V diagram of Carnot cycle: The process involves following prosses: 1-2:  Isothermal addition of…

Q: Refrigerant-134a is to be compressed from 0.14 MPa and –10°C to 0.8 MPa and 50°C steadily by a…

A: Given Data: The pressure at the compressor inlet is: P1= 0.14 MPa. The temperature at the…

Q: Steam enters an adiabatic turbine steadily at 400°C and 5 MPa and leaves at 20 kPa. The highest…

A: Given data: The temperature at inlet to the turbine is T1 = 400°C = (400°C + 273) K = 673 K The…

Q: Air enters the evaporator section of a window air conditioner at 100 kPa and 27°C with a volume flow…

A: On using table A-12, the enthalpy of Refrigerant-134a at the inlet of evaporator section is written…

Q: A heat engine that violate the Kelvin–Planck statement of the second law, Explain?

A:

Q: A completely reversible heat pump produces heat at a rate of 300 kW to warm a house maintained at…

A: Given Heat produced= 300 kW Temperature of the house = 24o C = 297K Temperature of the ambient = 7o…

Q: For adiabatic steady-flow devices, the vertical distance Δh on an h-s diagram is a measure of work,…

A: In adiabatic steady-flow devices, the enthalpy remains constant, and the process is called as…

Q: In a constant temperature, closed system process, 120 BTU of heat is transferred to the working…

A: Given:-  Closed system Constant temperature process Heat transfered (dQ) = 120 BTU = 126.607 kJ/kg…

Q: Long cylindrical steel rods (ρ = 7833 kg/m3 and cp = 0.465 kJ/kg·°C) of 10-cm diameter are heat…

A: To find  The rate of entropy generation Sgen. Given The density of the rod ρ is 7833 kg/m3. The…

Q: Q1/B/ Refrigerant-134a is to be compressed from 0.14 MPa and 10°C to 0.4 MPa and 40°C steadily by a…

A:

Q: Ambient air at 100 kPa and 300 K is compressed isentropically in a steady-flow device to 0.8 MPa.…

A: Given, P1 = 100 kPa  T1 = 300 K P2 = 0.8 MPa = 800 kPa Isentropic Process

Q: Cold water (cp = 4.18 kJ/kg⋅°C) leading to a shower enters a well-insulated, thin-walled,…

A: Given Data: The specific heat of cold water is cpc = 4.18 kJ/kg⋅°C. The inlet temperature of cold…

Q: A 250 MW adiabatic steam turbine operating with inlet conditions of 1750 psia and 1000°F and an exit…

A:

Q: Consider natural gas furnace, electric resistance heat pump systems. For a specified heating load,…

A: The irreversibility means the difference of maximum possible work to availability. Irreversibility…

Q: An inventor claims that a new fridge can operate between -15 degree Celsius and 150 degree C while…

A: Given:T2=-15°C =258 KT1=150°C =423 KHeat taken from sink,Q2=2200 WWork input,W=2000 W

Q: Demonstrate the validity of the Clausius inequality using a reversible and an irreversible heat…

A: Let's take two thermal engines R & IR as reversible and irreversible heat engine respectively.…

Q: Liquid water enters a pump at 100 kPa and 30°C at a rate of 1.35 kg/s and leaves at 4 MPa. If the…

A:

Q: During the isothermal heat rejection process of a Carnot cycle, the working fluid experiences an…

A: We have 1 Btu/R = 1.9×103 J/KEntropy Change of Working Fluid =-0.7 Btu/R = -0.7×1.9×103 =-1330…

Q: Liquid water enters an adiabatic piping system at 15°C at a rate of 8 kg/s. If the water temperature…

A: Given data: The initial temperature, T1 = 15oC. The rise in temperature, ∆T = 0.2oC. The mass flow…

Q: Make use of second law of thermodynamics to prove that two reversible adiabatic lines cannot…

A: Adiabatic Process - An adiabatic process is one in which the net heat interaction between the…

Q: Entropy change of Gas Turbine A gas turbine is used to harvest kinetic energy from superheated vapor…

A:

Q: Steam enters an adiabatic turbine at 3MPa and 500C and exits at 30 kPa. If the efficiency of the…

A:

Q: Air flows into an adiabatic nozzle at 500 kPa and 400K at a speed of 30 m/s and exits the nozzle at…

A:

Q: Air enters the evaporator section of a window air conditioner at 100 kPa and 27°C with a volume flow…

A: Ans(a) At inlet  h1=hliq.120+xhevap.120h1=22.47+0.3(214.52)=86.826KJ/Kg Heat transfer of refrigerant…

Q: Air is to be compressed steadily and isentropically from 1 atm to 16 atm by a two-stage compressor.…

A: Given data: The pressure of the air at the entry point of compressor is P1=1 atm The pressure of the…

Q: An inventor claims that a new refrigerator can operate between -15 o C and 150 o C while removing…

A:

Q: A refrigerator transfers 1kJ of heat from a cold region at -20°c to hot region at 30°c. If COP of…

A: Data given  QL = 1 kJ  TL = -20°C = 253 K  TH  = 30°C = 303 K  COP = 4

Q: Air is compressed steadily by a reversible compressor from an inlet state of 100 kPa and 300 K to an…

A: Obtain the pressure ratio.

Q: Hot combustion gases enter the nozzle of a turbojet engine at 230 kPa, 627°C, and 60 m/s and exit at…

A: Calculate the specific heat at constant volume. cv=cpk Here, the specific heat at constant pressure…

Entropy

In physics, entropy means the amount of disorder or the degree of randomness associated with a thermodynamic system. The system is not self-organized when the entropy of the system is high. For instance, when a system is at an elevated temperature, its molecules are in random motion, vibrating and colliding with each other. During this scenario, the probability of finding a molecule at a particular place twice, is low. Under this circumstance, the system can be said to be in a high entropy.