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In: Mechanical Engineering

A polytropic process (n= 1.25) compresses air from 0.3 m3 at 22 0C and pressure of...

A polytropic process (n= 1.25) compresses air from 0.3 m3 at 22 0C and pressure of 125 kPa to   0.15 m3. It is then expanded at constant temperature to its original volume.

  1. Sketch the P-V diagram                                                                                       [1 mark] Determine the;
  2. Mass of air                                                                                                          [2 marks]     
  3. Pressure at the end of the compression                                                           [2 marks]
  4. Final Temperature                                                                                             [2 marks]
  5. Net work                                                                                                            [4 marks]
  6. Net heat transfer                                                                                               [4 marks]

Solutions

Expert Solution

Drawing the P-V diagram carefully and then applying simple equation of every process we can solve this question. I have shown below-

samet mamat answered 1 year ago
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