A. higher effectiveness of boiler
B. high calorific value coal being burnt
C. fouling of heat transfer surfaces
D. raising of steam temperature
E. leakage of air
Related Mcqs:
- The maximum discharge through a chimney occurs when the height of chimney is_____________________?
A. infinitely long
B. around 200 meters
C. equal to the height of the hot gas column producing draught
D. outside temperature is very low
E. more than the tallest building nearby - The temperature of flue gases at air heater outlet should be__________________?
A. 100°C
B. above dew-point temperature of flue gases
C. below dew-point temperature of flue gases
D. less than wet bulb temperature of flue gases
E. above wet bulb temperature of flue gases - The pressure of reheat steam after passing through reheater compared to inlet condition is _________________?
A. more
B. less
C. equal
D. may be more or less depending on capacity of reheater
E. none of the above - One kg of steam sample contains 0.8 kg dry steam; it’s dryness fraction is__________________?
A. 0.2
B. 0.8
C. 1.0
D. 0.6
E. 0.5 - In an experiment to determine dryness fraction of steam, the mass of water separated was 1.2 kg in 15 mts and the mass of steam passed out in same time was 4.8 kg. Dryness fraction is__________________?
A. 40%
B. 25%
C. 50%
D. 80%
E. 90% - Expanding steam to a very low pressure (high vacuum) in steam engines is _________________?
A. desirable
B. economical
C. essential
D. optional
E. uneconomical - Vacuum for reciprocating steam engines compared to steam turbines is__________________?
A. more
B. equal
C. less
D. could be more or less depending on the size of plant
E. none of the above - The height of chimney in a power plant is governed by__________________?
A. the draft to be created
B. limitation of construction facilities
C. control of pollution
D. quantity of flue gases to be handled
E. all of the above - The saturation temperature of steam with increase in pressure increases____________________?
A. linearly
B. rapidly first and then slowly
C. slowly first and then rapidly
D. inversely
E. none of the above - Heating wet steam at constant temperature is heating it at constant_________________?
A. volume
B. pressure
C. entropy
D. enthalpy
E. none of the above
