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steam undergoes an adiabatic expansion in a piston-cylinder assembly from 100bar ,480\deg c to 1bar ,160\deg c. what is work in kj per kg of steam for the process? calculate the amount of entropy produced, in k(j)/(k)perkg of steam. what is the magnitude of the maximum theoretical work that could be obtained from the given initial state to the same final pressure?

User Adalpari
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Final answer:

To calculate the work done during an adiabatic expansion of steam in a piston-cylinder assembly, we can use the equation for the work done in an adiabatic process. To calculate the entropy produced during this process, we can use the equation. The maximum theoretical work that could be obtained from the given initial state to the same final pressure can be calculated using the equation.

Step-by-step explanation:

To calculate the work done during an adiabatic expansion of steam in a piston-cylinder assembly, we can use the equation for the work done in an adiabatic process:

W = (P1V1 - P2V2) / (y-1)

where P1 and P2 are the initial and final pressures, V1 and V2 are the initial and final volumes, and y is the ratio of specific heat capacities.

To calculate the entropy produced during this process, we can use the equation:

ΔS = ncv ln(T2/T1) + nR ln(V2/V1)

where ncV is the molar heat capacity at constant volume, n is the number of moles of steam, R is the ideal gas constant, T1 and T2 are the initial and final temperatures, and V1 and V2 are the initial and final volumes.

The maximum theoretical work that could be obtained from the given initial state to the same final pressure can be calculated using the equation:

Wmax = ΔU = ncV (T2 - T1)

User Bil Moorhead
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