Following observations were made after the trial of a boiler for 24 hours.Mass of coal burnt = 1300 kgMass of steam generated = 14000 kgMean effective pressure of steam = 10 barTemperature of the feed water = 40°CCalorific value of coal = 30000 kJ/kgCalculate the boiler efficiency if the dryness fraction of the steam generated is 0.95.

Following observations were made after the trial of a boiler for 24 h

1.	Following observations were made after the trial of a boiler for 24 hours.Mass of coal burnt = 1300 kgMass of steam generated = 14000 kgMean effective pressure of steam = 10 barTemperature of the feed water = 40°CCalorific value of coal = 30000 kJ/kgCalculate the boiler efficiency if the dryness fraction of the steam generated is 0.95.
A.	90%
B.	80%
C.	70%
D.	60%
Answer» B. 80%

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Following observations were made after the trial of a boiler for 24 hours.Mass of coal burnt = 1300 kgMass of steam generated = 14000 kgMean effective pressure of steam = 10 barTemperature of the feed water = 40°CCalorific value of coal = 30000 kJ/kgCalculate the boiler efficiency if the dryness fraction of the steam generated is 0.95.

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