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Steam Boilers, Engines, Nozzles And Turbines MCQ
480 Important Steam Boilers, Engines, Nozzles And Turbines MCQ Question and Answer | PDF Free Download
1.In turbines, the fluid undergoes a continuous steady flow process and the speed of flow is
- ALow
- BVery low
- CHigh
- DVery high
2.The critical pressure ratio for initially superheated steam is __________ as compared to initially dry saturated steam.
- AMore
- BLess
- CSame
- DNone of these
3.The isentropic enthalpy drop in moving blade is two-third of the isentropic enthalpy drop in fixed blades of a turbine. The degree of reaction will be
- A0.4
- B0.56
- C0.67
- D1.67
4.In a reaction turbine
- AThe steam is allowed to expand in the nozzle, where it gives a high velocity before it enters the moving blades
- BThe expansion of steam takes place partly in the fixed blades and partly in the moving blades
- CThe steam is expanded from a high pressure to a condenser pressure in one or more nozzles
- DThe pressure and temperature of steam remains constant
5.By compounding the expansion of steam in two or more cylinders, the length of stroke
- ADoes not change
- BIncreases
- CDecreases
- DNone of these
6.The working pressure range for a LaMont boiler is
- A0.5 to 10 MN/m²
- B1 to 15 MN/m²
- C2.5 to 15 MN/m²
- D3.5 to 20 MN/m²
7.1 kg.m is equal to
- A9.81 Joules
- B102 Joules
- C427 Joules
- DNone of these
8.The function of a cross-head is to guide motion of the _________ and to prevent it from bending.
- APiston rod
- BConnecting rod
- CEccentric rod
- DValve rod
9.The draught in locomotive boilers is produced by a
- AChimney
- BCentrifugal fan
- CSteam jet
- DNone of these
10.Which is not correct statement about effect of sulphur in fuel?
- AIt has heating value
- BIt helps in electrostatic precipitation of ash in flue gases
- CIt leads to corrosion of air heaters, ducting, etc. if flue gas exit temperature is low
- DIt erodes furnace walls
11.The principal function of a stop valve is to
- AControl the flow of steam from the boiler to the main pipe and to shut off the steam completely when required
- BEmpty the boiler when required and to discharge the mud, scale or sediments which are accumulated at the bottom of the boiler
- CPut off fire in the furnace of the boiler when the level of water in the boiler falls to an unsafe limit
- DIncrease the temperature of saturated steam without raising its pressure
12.The best suited coal for chain or traveling grate stoker boiler is
- ACoking coal
- BNon-coking or free burning coal
- CPulverized coal
- DHigh sulphur coal
13.The action of steam in a steam turbine is
- AStatic
- BDynamic
- CStatic and dynamic
- DNeither static nor dynamic
14.Superheating of steam is done at
- AConstant volume
- BConstant temperature
- CConstant pressure
- DConstant entropy
15.Proximate analysis of fuel is determination of percentage of
- ACarbon, hydrogen, nitrogen, sulphur, moisture
- BFixed carbon, ash, volatile matter, moisture
- CHigher calorific value
- DLower calorific value
16.Ultimate analysis of fuel is determination of percentage of
- ACarbon, hydrogen, nitrogen, sulphur, moisture
- BFixed carbon, ash, volatile matter, moisture
- CHigher calorific value
- DLower calorific value
17.The function of a flywheel is
- ATo convert reciprocating motion of the piston into rotary motion
- BTo convert rotary motion of the crankshaft into to and fro motion of the valve rod
- CTo prevent fluctuation of speed
- DTo keep the engine speed uniform at all load conditions
18.A device used to put off fire in the furnace of the boiler when the level of water in the boiler falls to an unsafe limit, is called
- ABlow off cock
- BStop valve
- CSuperheater
- DNone of these
19.The reheat factor is the ratio of the
- ACumulative heat drop to the isentropic heat drop
- BIsentropic heat drop to the heat supplied
- CTotal useful heat drop to the total isentropic heat drop
- DNone of the above
20.Duplex feed pumps are used in small steam boilers. These operate on the principle of
- ACentrifugal pump
- BAxial flow pump
- CGear pump
- DReciprocating pump