POWER PLANT ENGG MCQ PART 2

 

21.    In a regenerative feed heating cycle, the greatest economy is affected

(a)     when steam is extracted from only one suitable point of steam turbine
(b)     when steam is extracted from several places in different stages of steam turbine
(c)    when steam is extracted only from the last stage of steam turbine
(d)    when steam is extracted only from the first stage of steam turbine

Ans: b

 

22.    The maximum percentage gain in Regenerative feed heating cycle thermal efficiency

(a)    increases with number of feed heaters increasing
(b)    decreases with number of feed heaters increasing
(c)    remains same unaffected by number of feed heaters
(d)    none of the above

Ans: a

 

23.    In regenerative cycle feed water is heated by

(a)     exhaust gases
(b)     heaters
(c)    draining steam from the turbine
(d)    all above

Ans: c

 

24.    Reheat cycle in steam power plant is used to

(a) utilize heat of flue gases
(b) increase thermal efficiency
(c) improve condenser performance
(d) reduce loss of heat

Ans: b

 

25.    Mercury is a choice with steam in binary vapour cycle because it has

(a)     higher critical temperature and pressure
(b)     higher saturation temperature than other fluids
(c)    relatively low vaporization pressure
(d)    all above

Ans: d

                             

26.    Binary’vapour cycles are used to

(a) increase the performance of the condenser
(b) increase the efficiency of the plant
(c) increase efficiency of the turbine

Ans: b

 

27.    A steam power station requires space

(a)    equal to diesel power station
(b)    more than diesel power station
(c)    less than diesel power station

Ans: b

 

28.    Economizer is used to heat

(a)    air
(b)    feed water
(c)    flue gases
(d)    all above

Ans: b

 

29.    The modern steam turbines are

(a)    impulse turbines
(b)    reaction turbines
(c)    impulse-reaction turbines
(d)    none of the above

Ans: c

                                     

30.    The draught which a chimney produces is called

(a)     induced draught
(b)     natural draught
(c)    forced draught
(d)    balanced draught

Ans: b

 

31.    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

Ans: b

 

32.    In a boiler installation the natural draught is produced

(a)    due to the fact that furnace gases being light go through the chimney giving place to cold air from outside to rush in
(b)    due to the fact that pressure at the grate due to cold column is higher than the pressure at the chimney base due to hot column
(c)    due to the fact that at the chimney top the pressure is more than its environmental pressure
(d)    all of the above

Ans: b

 

33.    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

Ans: a

 

34.    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

Ans: b

 

35.    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

Ans: b

 

36.    Artificial draught is produced by

(a)     induced fan
(b)     forced fan
(c)     induced and forced fan
(d)     all of the above

Ans: d

 

37.    The draught in locomotive boilers is produced by

(a)     forced fan
(b)     chimney
(c)     steam jet
(d)     only motion of locomotive

Ans: c

 

38.    For the same draught produced the power of induced draught fan as compared to forced draught fan is

(a)     less
(b)     more
(c)     same
(d)     not predictable

Ans: b

 

39.    Artificial draught is produced by

(a)     air fans
(b)     steam jet
(c)    fan or steam jet
(d)    all of the above

Ans: d

 

40.    The artificial draught normally is designed to produce

(a)     less smoke
(b)     more draught
(c)    less chimney gas temperature
(d)    all of the above

Ans: d