Answer:
The first T-s diagram shows the steam turbine producing power using non-superheated steam and the other T-s diagram shows the steam turbine producing power using superheated steam.
In the case of superheating the dryness factor at the exit of the turbine is higher. The turbine life will be higher in this case because of the higher dryness fraction.
Ideally, the dryness fraction should be 1 at the turbine exit.
Superheated steam produces more amount of work comparatively and increases thermal efficiency.
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