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Thermodynamics

Question
CBSEENPH11026398

A Carnot engine operates with source at 127°C and sink at 27°C. If the source supplies 40 kJ of heat energy, the work done by the engine is

  • 30 kJ

  • 10 kJ

  • 4 kJ

  • 1 kJ

Solution

B.

10 kJ

Efficiency, η = 1 - T2T1

              η = 1 - 273 + 27273 + 127

              η  = 1 - 300400 

                   = 1 -34

              η  = 14

Also, The efficiency defination given by

        η  = Work done by engineHeat supplied by source

             = W40 kJ

∴   W = 40 η 

           = 40 × 14

     W = 10 kJ