The efficiency of chimney is approximately______________?

Related Mcqs:

1. The draught produced by steel chimney as compared to that produced by brick chimney for the same height is_____________?

   A. less
   B. more
   C. same
   D. may be more or less

2. The draught produced, for a given height of the chimney and given mean temperature of chimney gases_______________?

   A. decreases with increase in outside air temperature
   B. increases with increase in outside air temperature
   C. remains the same irrespective of outside air temperature
   D. may increase or decrease with increase in outside air temperature

3. The energy radiated by sun on a bright sunny day is approximately______________?

   A. 700 W/m2
   B. 800 W/m2
   C. 1 kW/m2
   D. 2 kW/m2

4. The overall efficiency of a steam power station is ________ its thermal efficiency.

   A. less than
   B. equal to
   C. greater than
   D. none of the above

5. The draught which a chimney produces is called_____________?

   A. induced draught
   B. natural draught
   C. forced draught
   D. balanced draught

6. The draught produced by chimney of given height at given outside temperature___________?

   A. decreases if the chimney gas temperature increases
   B. increases if the chimney gas temperature increases
   C. remains same irrespective of chimney gas temperature
   D. may increase or decrease

7. For forced draught system, the function of chimney is mainly_____________?

   A. to produce draught to accelerate the combustion of fuel
   B. to discharge gases high up in the atmosphere to avoid hazard
   C. to reduce the temperature of the hot gases discharged
   D. none of the above

8. Rankine efficiency of a steam power plant____________?

   A. improves in summer as compared to that in winter
   B. improves in winter as compared to that in summer
   C. is unaffected by climatic conditions
   D. none of the above

9. The thermal efficiency of the engine with condenser as compared to without condenser, for a given pressure and temperature of steam, is_____________?

   A. higher
   B. lower
   C. same as long as initial pressure and temperature is unchanged
   D. none of the above

10. Economisers improve boiler efficiency by__________?

    A. 1 to 5%
    B. 4 to 10%
    C. 10 to 12%