steam boilers engines nozzles and turbines Mcqs
1. For water, at pressures below atmospheric___________________?
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A. melting point drops slightly and boiling point drops slightly

B. melting point rises slightly and boiling point drops markedly

C. melting point rises markedly and boiling point drops markedly

D. melting point drops slightly and boiling point drops markedly

E. none of the above

2. The function of injector used in small steam plants is to________________?
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A. control steam temperature by injecting water

B. dose chemicals in feed water

C. create vacuum in furnace

D. create vacuum at turbine exhaust

E. pump feed water
3. The diameter of fire tube of Cornish boiler compared to its shell is__________________?
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A. three-fifth

B. one-fifth

C. two-fifth

D. one third

E. one half
4. Hard coke is produced by carborisation of coal at_______________?
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A. 120O-1500C

B. 70O-850C

C. 95O-1100C

D. atmospheric temperature

E. 500-600C

5. Which of the following is a water tube boiler_________________?
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A. Cochran boiler

B. locomotive boiler

C. Lancashire boiler

D. Cornish boiler

E. Babcock and Wilcox boiler
6. Hard coke is used in________________?
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A. cement industry

B. locomotives

C. blast furnace

D. thermal power plant

E. domestic use

7. Lancashire boiler is a__________________?
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A. water tube boiler with natural/forced circulation

B. none of the above

C. stationary fire tube boiler

D. mobile fire tube boiler

E. stationary water tube boiler

8. On Mollier chart, free expansion, or throttling process from high pressure to atmosphere is represented by_______________?
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A. curved line

B. vertical straight line

C. none of the above

D. straight inclined line

E. horizontal straight line
9. Latent heat of dry steam at atmospneric pressure is equal to____________________?
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A. 100 kcal/kg

B. 427 kcal/kg

C. 539 BTU/lb

D. 471 kcal/kg

E. 539 kcal/kg
10. 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__________________?
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A. 40%

B. 50%

C. 80%

D. 90%

E. 25%

11. Heating wet steam at constant temperature is heating it at constant_________________?
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A. enthalpy

B. pressure

C. none of the above

D. entropy

E. volume

12. At very low temperature, the melting and boiling temperatures become equal. This temperature is____________________?
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A. 0K.

B. 300K

C. 373K

D. 273.16K

E. 303K

13. 100% efficiency of a thermal cycle cannot be achieved because of __________________?
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A. non-availability of ideal substance

B. frictional losses

C. it is not possible to achieve 0K temperature

D. leakage

E. none of the above

14. The saturation temperature of steam with increase in pressure increases____________________?
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A. linearly

B. inversely

C. slowly first and then rapidly

D. rapidly first and then slowly

E. none of the above

15. A packaged boiler is one in which various parts like firing equipment, fans, feed pumps and automatic controls are________________?
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A. none of the above

B. supplied by same manufacturer loose and assembled at site

C. packaged boiler does not exist

D. supplied mounted on a single base

E. purchased from several parties and packed together at site

16. The specific volume of steam with increase in pressure decreases_____________________?
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A. slowly first and then rapidly

B. linearly

C. none of the above

D. rapidly first and then slowly

E. inversely

17. Which of the following gases has the highest calorific value ________________?
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A. producer gas

B. coal gas

C. blast furnace gas

D. coke oven gas

E. water gas

18. The water tubes in a babcock and wilcox boiler are__________________?
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A. vertical

B. horizontal

C. horizontal and inclined

D. inclined

E. vertical and inclined

19. The shell diameter and length of locomotive boiler are_______________?
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A. 1.5 m, 8 m

B. 1.5 m, 4 m

C. 2 m, 4 m

D. 1 m, 4 m

E. 1.5 m, 6 m

20. Which of the following varieties of coals is mostly used in steam boilers____________________?
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A. peat

B. non-coking bituminous coal

C. none of the above

D. brown coal

E. coking bituminous coal

21. The biggest size of thermal power unit operating in India is ________________?
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A. 60 MW

B. 100 MW

C. 500 MW

D. 210 MW

E. 30 MW

22. The fire tubes in, a Coarran and Scotish marine boiler are_________________?
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A. horizontal

B. vertical

C. inclined

D. both horizontal and vertical

E. horizontal and inclined

23. Efficiency of a thermal cycle increases by ________________?
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A. regeneration

B. reheating of steam

C. both A. and B.

D. cooling of steam

E. none of the above

24. The diameter of tubes for natural circulation boiler as compared to controlled circulation boilers is___________________?
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A. same

B. could be more or less depending on other factors

C. none of the above

D. more

E. less

25. Which of the following is steam dbal?
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A. non-coking bituminous coal

B. pulverised coal

C. none of the above

D. coking bituminous coal

E. brown coal

26. The specific heat of superheated steam in kcal/kg is generally of the order of___________________?
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A. 0.1

B. 0.5

C. 1

D. 0.8

E. 0.3

27. Superheating of steam is done at_________________?
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A. constant pressure

B. constant entropy

C. constant enthaply

D. constant volume

E. constant temperature

28. Mechanical equivalent of heat for 1 kcal or Joules equivalent is equal to_________________?
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A. 102 kgm

B. 75 kgm

C. 539 kgm

D. 421 kgm

E. 421 kgm
29. The diameters of fire tubes and superheaer tubes in locomotive boiler are_________________?
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A. 32.5 mm, 180 mm

B. 65.5 mm, 210 mm

C. 47.5 mm, 130 mm

D. 24.5 mm, 65 mm

30. During polytropic process_________________?
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A. steam may be wet, dry or superheated after expansion

B. work is done

C. none of the above

D. all of the above

E. heat transfer takes place across cylinder walls

31. The dry saturated steam at very high pressure (150-200 kg/cm2) when throttled to atmosphere will become_______________?
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A. remain dry saturated

B. wet

C. none of the above

D. superheated

E. dry

32. Water boils when its vapour pressure ___________________?
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A. equals 760 mm of mercury

B. equals to atmospheric pressure

C. equals that of the surroundings

D. boiling has ^nothing to do with vapour pressure

E. equals the pressure of water in the container

33. A boiler in India should conform to safety regulations of__________________?
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A. BS

B. DIN

C. GOST

D. IBR

E. ASTM

34. In a throttling process_________________?
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A. internal energy of steam changes

B. all of the above

C. none of the above

D. work is done by the expanding steam

E. heat transfer takes place

35. Carbonation of coal is the process of________________________?
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A. heating wood in a limited supply of air at temperatures below 300C

B. binding the pulverised coal into brick-ettes

C. strongly heating coal continuously for about 48 hours in the absence of air in a closed vessel

D. enriching carbon in the coal

E. pulverising coal in inert atmosphere

36. Pick up the correct statement as regards Cornish boiler and Lancashire boiler _______________?
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A. cornish is fire tube and lancashire is water tube

B. cornish is water tube and lancashire is fire tube

C. cornish has two fire tubes and lancashire has one

D. lancashire has two fire tubes and cornish has one

E. both have two fire tubes

37. Efficiency of rankine cycle can be increased by_________________?
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A. decreasing exhaust pressure

B. increasing number of regenerative heaters

C. decreasing initial steam pressure and temperature

D. increasing exhaust pressure

E. increasing the expansion ratio

38. The coal requirement per kW hour generation in the thermal power plant is of the order of__________________?
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A. 1.5 to 2 kg

B. 0.2 to 0.4 kg

C. 1.0 to 1.5 kg

D. 0.6 to 0.8 kg

E. 0.1 to 0.2 kg

39. Coke is produced by__________________?
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A. enriching carbon in the coal

B. pulverising coal in inert atmosphere

C. strongly heating coal continuously for about 48 hours in the absence of air in a closed vessel

D. heating wood in a limited supply of air at temperatures below 300GC

E. binding the pulverised coal into brick-etts

40. Stoichiometric quantity of air is the___________________?
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A. air required for optimum combustion so as to have reasonable excess air

B. air present in atmosphere at NTP conditions

C. air required to convert CO into C02

D. air required to form an explosive mixture

E. air required for complete combustion of fuel with no excess air
41. The dry saturated steam at very low pressure, (5-10 kg/cm2) when throttled to atmosphere will become________________?
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A. wet

B. none of the above

C. superheated

D. remain dry satruated

E. dry

42. The increase in pressure _________________?
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A. raises the boiling point of a liquid

B. lowers the boiling point of a liquid

C. none of the above

D. .does not affect the boiling point of a liquid

E. reduces its volume

43. Which of the following substance will have same percentage in both proximate and ultimate analysis___________________?
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A. ash

B. volatile matter

C. moisture

D. hydrogen

E. none of the above

44. The basic purpose of drum in boiler is to_____________________?
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A. serve as storage of feed water for water wall

B. control level

C. serve as storage of steam

D. remove salts from water

E. separate steam from water
45. While steam expands in turbines, theoretically the entropy________________?
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A. decreases

B. remains constant

C. none of the above

D. increases

E. behaves unpredictably

46. For burning 1 kg of carbon to CO as per chemically correct combusiton, amount of air required is___________________?
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A. 8/3kg

B. 2 kg

C. 4/3kg

D. 1 kg

E. 16/3 kg

47. In locomotive boiler, maximum steam pressure is limited to_______________?
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A. 31 kg/cm2

B. 1 kg/cm2

C. 18 kg/cm2

D. 5 kg/cm2

E. 10 kg/cm2

48. The high pressure boiler is oiie producing steam at a pressure more than_________________?
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A. 5 kg/cm2

B. 75-80 kg/cm2

C. 10 kg/cm2

D. 40 kg/cm2

E. atmospheric pressure

49. Sublimation region is the region where__________________?
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A. solid and vapour phases are in equi-librium

B. liquid and vapour phases are in equilibrium

C. solid, liquid and vapour phases are in equilibrium

D. none of the above

E. solid and liquid phases are in equilibrium

50. Equivalent evaporation is the amount of water evaporated in a boiler from and at ____________________?
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A. room temperature

B. 100C

C. saturation temperature at given pressure

D. 0C

E. 20C