Power Plant Engineering MCQs Quiz Multiple Choice Questions & Answers

1. The overall efficiency of a boiler in a thermal power plant is of the order of

1. 10%
2. 25 to 30%
3. 40 to 50%
4. 70 to 80%.

2. Permissible pH value of water for boilers is

1. 1
2. 7
3. slightly more than 7
4. 10

3. Heating value of coal is approximately

1. 1000-2000 kcal / kg
2. 2000-4000 kcal / kg
3. 5000-6500 kcal / kg
4. 9000-10,500 kcal / kg

4. The steam consumption per kWh of electricity generated in a modem power plant is of the order of

1. 1-2 kgs
2. 2-4 kgs
3. 5-7 kgs
4. 10-12 kgs.

5. What is the maximum size of steam turbine usually being installed, for thermal power plants ?

1. 120 MW
2. 250 MW
3. 500 MW
4. 1000 MW.

6. Which of the following is not the voltage at which power is usually transmitted(A)132 kV

1. 132kV
2. 66 kV
3. 33 kV
4. 20 kV.

7. Overall thermal efficiency of a steam power station is in the range

1. 18-24%
2. 30-40%
3. 44-62%
4. 68-79%.

8. Most of the generators in thermal power plants run at

1. 3000 rpm
2. 1500 rpm
3. 1000 rpm
4. 750 rpm.

9. Standard frequency usually for electric supply is

1. 50 Hz
2. 60 Hz
3. 50 to 60 Hz
4. 50 to 55 Hz.

10. A 100 MW thermal power-plant will consume nearly how many tonnes of coal in one hour ?

1. 50 tonnes
2. 150 tonnes
3. 1500 tonnes
4. 15,000 tonnes.

11. Soot is virtually nothing but

1. ash
2. cinder
3. gas
4. carbon4

12. Super heated steam is always

1. at a temperature higher than the saturation temperature corresponding to a steam pressure
2. at a pressure more than the boiler steam pressure
3. separated from water particles before being supplied to turbine
4. at a pressure less than the maximum cycle pressure.

13. Water is supplied to a boiler

1. at atmospheric pressure
2. at slightly more than atmospheric pressure
3. at 100 cm/kg2
4. at more than the steam pressure on the boiler.

14. Pressure of steam in condenser is

1. atmospheric pressure
2. more than pressure
3. slightly less than pressure
4. much less than pressure.

15. Equipment used for pulverizing the coal is known as

1. Ball mill
2. Hopper
3. Burner
4. Stoker.

16. Which of the following is considered as superior quality of coal ?

1. Bituminous coal
2. Peat
3. Lignite
4. Coke.

17. Which coal will have highest ash content ?

1. Bituminous coal
2. Grade I steam coal
3. Coking coal
4. Lignite.

18. Burning of low grade fuel can be improved by

1. Blending with better quality
2. Oil assisted ignition
3. Pulverizing
4. Any of the above.

19. A condenser in a thermal power plant condenses steam combing out of

1. Boiler
2. Super-heater
3. Economizer
4. Turbine.

20. In a power plant, coal is carried from storage place to boilers generally by means of

1. bucket
2. belts
3. trolleys
4. manually.

21. Pulverized coal is

1. coal free from ash
2. non-smoking coal
3. coal which bums For long time
4. coal broken into fine particles.

22. Live storage of coal in a power plant means

1. coal ready for combustion
2. preheated coal
3. storage of coal sufficient to meet 24 hour demandof the plant
4. coal in transit.

23. Which of the following enters the super heater of a boiler ?

1. Cold water
2. Hot water
3. Wet steam
4. Super-heated steam.

24. In regenerative cycle, bled steam is

1. discharged to atmosphere
2. condensed in steam condenser
3. used to beat feed water for boiler
4. is mixed with steam supplied to turbine.

25. When pulverized fuel is not used, the equipment used for supplying coal to the boiler is

1. Heater
2. Stoker
3. Burner
4. Skip hoist.

26. The efficiency of a thermal power plant improves with

1. increased quantity of coal burnt
2. larger quantity of water used
3. lower load in the plant
4. use of high steam pressures.

27. The equipment installed in power plants to reduce air pollution due to smoke is

1. Induced draft fans
2. De-super heaters
3. Electrostatic precipitators
4. Re-heaters.

28. As steam expands in turbine

1. its pressure increases
2. its specific volume increases
3. its boiling point increases
4. its temperature increases.

29. For low head and high discharge, the hydraulic turbine used is

1. Kaplan turbine
2. Francis turbine
3. Pelton wheel
4. Jonual turbine.

30. Which of the following, is not a high pressure boiler ?

1. Loeffler boiler
2. Lancashire boiler
3. Velox boiler
4. Lamont boiler.

31. Low grade fuels have

1. low moisture content
2. low ash content
3. low calorific value
4. low carbon content.

32. Bagasse is

1. low quality coal
2. a fuel consisting of wood
3. fibrous portion of sugarcane left after extracting the juice
4. a kind of rice straw.

33. Power plants using coal work closely on known which of the following cycle ?

1. Otto cycle
2. Binary vapor cycle
3. Brayton cycle
4. Rankine cycle.

34. Chemical composition of coal is given by

1. Proximate analysis
2. Ultimate analysis
3. Orast analysis
4. All of the above.

35. Which of the following contributes to the improvement of efficiency of Rankine cycle in a thermal power plant ?

1. Reheating of steam at intermediate stage
2. Regeneration use of steam for heating boiler feedwater
3. Use of high pressures
4. All of the above.

36. In power station practice spinning reserve is

1. reserve generating capacity that is in operation but not in service
2. reserve generating capacity that is connected to bus and ready to take the load
3. reserve generating capacity that is available for service but not in operation
4. capacity of the part of the plant that remains under maintenance.

37. In a steam locomotive the engine is

1. Single cylinder
2. Vertical
3. Condensing
4. Non-condensing.

38. Ash content of coal can be reduced by

1. slow burning
2. washing
3. pulverizing
4. mixing with high grade coal.

39. Coal used in power plant is also known as

1. steam coal
2. charcoal
3. coke
4. soft coal.

40. Which variety of coal has lowest calorific value?

1. Steam-coal
2. Bituminous coal
3. Lignite
4. Anthracite.

41. Out of the following which one is not a unconventional source of energy ?

1. Tidal power
2. Geothermal energy
3. Nuclear energy
4. Wind power

42. In a steam turbine cycle, the lowest pressure occurs in

1. turbine inlet
2. boiler
3. condenser
4. super heater.

43. The boilers using lignite as fuel do not use

1. under feed stoker
2. traveling grate stoker
3. spreader stoker
4. all of the above.