Reversible expansion according to a law pv^2 = constant

In summary, a fluid undergoes a reversible compression at a constant pressure of 0.7bar to 3.5bar, followed by a reversible heating at constant volume to 4bar. It then undergoes a reversible expansion to return to its initial state. The cycle is shown on a p-v diagram and the following values can be calculated: I. The mass of the fluid present is 0.0753kg. II. The value of n in the first process is 1.847. III. The net work of the cycle is -640.
  • #1
megasima2006
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A fluid at 0.7bar occupying 0.009m3 is compressed reversibly to a pressure of 3.5bar according to a law pv^n = constant. The fluid is then heated reversibly at constant volume until the pressure is 4bar; the specific volume is then 0.5m3/kg . A reversible expansion according to a law pv^2 = constant restores the fluid to its initial state. Sketch the cycle on a p-v diagram and calculate:
I. The mass of fluid present
II. The value of n in the first process
III. The net work of the cycle
Answers:
0.0753kg; 1.847; -640
 
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  • #2
need to solve this question before my exam period.
thanks for helping
 

1. What is reversible expansion?

Reversible expansion is a type of thermodynamic process in which a system expands or contracts without any loss of energy or heat to the surroundings.

2. What is the law pv^2 = constant?

The law pv^2 = constant, also known as the Boyle's law, states that at a constant temperature, the product of pressure and the square of the volume of a gas is always constant.

3. How does reversible expansion follow the law pv^2 = constant?

In reversible expansion, the pressure and volume of the gas change in such a way that the product of the two remains constant. This means that as the volume increases, the pressure decreases and vice versa.

4. What are some examples of reversible expansion?

One example of reversible expansion is the expansion of a gas in a piston-cylinder system without any friction or heat loss. Another example is the expansion of a gas in a balloon.

5. How is reversible expansion different from irreversible expansion?

In reversible expansion, the system returns to its original state after the expansion is reversed, while in irreversible expansion, the system does not return to its original state and some energy is lost to the surroundings.

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