Entropy is:
Entropy of a system:
When a system reaches the state of equilibrium, the following property assumes its maximum value:
Area of the curve on T-S curve when projected on entropy axis gives:
Which of the following curve represents Carnot cycle on T-S curve?
Which of the following relation about entropy change is not correct?
Entropy charge in adiabatic process is:
The latent heat of fusion of water at 0oC is 335 kJ/kg. How much does the entropy of a 1 kg of ice change as it melts into water in each of the following ways:
(a) Heat is supplied reversibly to a mixture of ice and water at 0oC.
(b) A mixture of ice and water at 0oC is stirred by a paddle wheel.
Two kg of water at 80oC are mixed adiabatically with 3 kg of water at 30oC in a constant pressure process of 1 atmosphere. Find the increase in the entropy of the total mass of water due to the mixing process (cp of water = 4.187 kJ/kg K).
Loss in available energy is due to:
Gibb’s function is expressed as:
Availability function is expressed as:
What is the maximum useful work which can be obtained when 100 kJ are abstracted from a heat reservoir at 675 K in an environment at 288 K?
Exhaust gases leave an internal combustion engine at 800oC and 1 atm, after having done 1050 kJ of work per kg of gas in the engine (cp of gas = 1.1 kJ/kg K). The temperature of the surroundings is 30oC.
How much available energy per kg of gas is lost by throwing away the exhaust gases?
Assertion (A): When a gas is forced steadily through an insulated pipe containing a porous plug, the enthalpy of gas is the same on both sides of the plug.
Reason (R): The gas undergoes an isentropic expansion through the porous plug.
What is the loss of available energy associated in the transfer of 1000 kJ of heat from a constant temperature system at 600 k to another at 400 k and the ambient temperature is 300 k?
For a steady flow process from state 1 to state 2 enthalpy change from h1=400kJ/kg to h2=100 kJ/kg and entropy change from S1= 1.1 kJ/kg-k to S2= 0.7 kJ/kg-k and ambient temperature T0=300 k then change in availability is:
What is the formula for irreversibility?
In a steam generator, water is evaporated at 260oC, while the combustion gas (cp = 1.08 kJ/kg K) is cooled from 1300oC to 320oC. The surroundings are at 30oC. Determine the loss in available energy due to the above heat transfer per kg of water evaporated (Latent heat of vaporization of water at 260oC = 1662.5 kJ/kg).
As mentioned in above figure region (1), (2), (3) are
The point at which saturated liquid and saturated vapour line meet is called:
Which of the following does not represents Clausius Clapeyron equation.
Heat transfer associated with Phase change is called:
Boiler steam at 8 bar, 250oC, reaches the engine control valve through a pipeline at 7 bar, 200oC. It is throttled to 5 bar before expanding in the engine to 0.1 bar, 0.9 dry. Determine per kg of steam the heat loss in the pipeline. (at P=8 bar, T=2500C enthalpy=2950.1 kJ/kg and at p=7 bar, T=2000C enthalpy=2844.8 kJ/kg)
On P-V diagram, triple point is
