In thermodynamics, the interaction whose external system could be viewed as the raising of mass through a distance against gravitational force is defined as work done by a system on the surroundings during a process.
Thermodynamics Formulas are listed below.
Some thermodynamic functions cannot be calculated straightforwardly. One needs to be able to present these quantities regarding others that can be experimentally determined.
Problem 1: Calculate how much heat is either added or removed from the system when 100kJ of work is done on a closed system during a process and the total energy of the system increases by 55.0kJ.?
By the energy conservation principle, a gross energy transfer to system effects in an equivalent increase of internal energy stockpiled in the system. This may be articulated as
Q = DeltaE + W
This equation is typical statement of first law. It says that in any alteration of state the heat supplied to a system is equal to the work finished by the system plus the upsurge of internal energy in the system.
Bearing in mind the work is done on a system as positive
Q + (+100.0) = +55.0
Q = +55.0 – 100.0
Q = -45.0kJ
From the result owing to the negative sign 45.0kJ of energy in heat form is removed from the system all through the procedure.
Problem 2: For a pound of Freon 12 refrigerant calculate the work done during compression. The refrigerant is at 20 psia and 30oF and is compressed to 140 psia and 150oF during a compression stroke.
From the table of thermodynamic properties for refrigerent 12 the unique and concluding specific volumes are 2.0884 and 0.33350 cu ft/lb respectively. For the procedure
frac14020 = left(frac2.08840.33350right)2
7 = (6.262)n
n = 1.0607
The work done in compression =
W = fracP2V2–P1V11−n
W = frac1441−1.067 times (140 times 0.3335-20 times 2.0884)
W = -11,670ft-1b