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Compressors, Gas Turbines And Jet Engines MCQ
300 Important Compressors, Gas Turbines And Jet Engines MCQ Question and Answer | PDF Free Download
1.The ratio of the net work obtained from the gas turbine plant to the turbine work is known as
- ACompression ratio
- BWork ratio
- CPressure ratio
- DNone of these
2.Free air is the air at
- AAtmospheric conditions at any specific location
- B20°C and 1 kg/cm² and relative humidity of 36%
- C0°C and standard atmospheric conditions
- D15°C and 1 kg/cm²
3.Standard air is the air at
- AAtmospheric conditions at any specific location
- B20°C and 1 kg/cm² and relative humidity 36%
- C0°C and standard atmospheric conditions
- D15°C and 1 kg/cm²
4.The overall efficiency of the compressed air system is the
- ARatio of shaft output of the air motor to the shaft input to the compressor
- BRatio of shaft input to the compressor to the shaft output of air motor
- CProduct of shaft output of air motor and shaft input to the compressor
- DNone of the above
5.In a jet engine, the air-fuel ratio is
- A30:1
- B40:1
- C50:1
- D60:1
6.The reason for volumetric efficiency of reciprocating compressor being less than 100 percent is
- APressure drop across the valves
- BSuperheating in compressor
- CClearance volume and leakages
- DAll of these
7.The ratio of isentropic work to Euler work is known as
- APressure coefficient
- BWork coefficient
- CPolytropic reaction
- DSlip factor
8.The ratio of isentropic work to Euler’s work is known as
- ACompressor efficiency
- BIsentropic efficiency
- CPolytropic reaction
- DSlip factor
9.In a single acting reciprocating compressor, the suction, compression and delivery of air takes place in ________ of the piston.
- AOne stroke
- BTwo strokes
- CThree strokes
- DFour strokes
10.The overall thermal efficiency of an ideal gas turbine plant is (where r = Pressure ratio)
- Ar ɣ-1
- B1 - r ɣ-1
- C1 - (1/r) ɣ-1/ɣ
- D1 - (1/r) ɣ/ɣ-1
11.Water gas is produced by
- ACarbonisation of coal
- BPassing steam over incandescent coke
- CPassing air and a large amount of steam over waste coal at about 65°C
- DPartial combustion of coal, eke, anthracite coal or charcoal in a mixed air steam blast
12.Producer gas is produced by
- ACarbonisation of coal
- BPassing steam over incandescent coke
- CPassing air and a large amount of steam over waste coal at about 65°C
- DPartial combustion of coal, coke, anthracite coal or charcoal in a mixed air steam blast
13.The criterion of the thermodynamic efficiency for rotary compressor is
- AIsentropic compression
- BIsothermal compression
- CPolytropic compression
- DNone of the above
14.Gas turbines for power generation are normally used
- ATo supply base load requirements
- BTo supply peak load requirements
- CTo enable start thermal power plant
- DIn emergency
15.Turbofan engine employs
- AOne air stream
- BTwo or more air streams
- CNo air stream
- DSolid fuel firing
16.The maximum propulsion efficiency of a turbojet is attained at around following speed
- A550 km/hr
- B1050 km/hr
- C1700 km/hr
- D2400 km/hr
17.The work ratio of a gas turbine plant is defined as the ratio of
- ANet work output and heat supplied
- BNet work output and work done by turbine
- CActual heat drop and isentropic heat drop
- DNet work output and isentropic heat drop
18.The overall isothermal efficiency of compressor is defined as the ratio of
- AIsothermal h.p. to the BHP of motor
- BIsothermal h.p. to adiabatic h.p.
- CPower to drive compressor to isothermal h.p.
- DWork to compress air isothermally to work for actual compression
19.The overall isothermal efficiency of the compressor is defined as the ratio of
- AWork required to compress the air isothermally to the actual work required to compress the air for the same pressure ratio
- BIsothermal power to the shaft power or B.P. of the motor or engine required to drive the compressor
- CVolume of free air delivery per stroke to the swept volume of the piston
- DIsentropic power to the power required to drive the compressor
20.The compressed air may be used
- AIn gas turbine plants
- BFor operating pneumatic drills
- CIn starting and supercharging of I.C. engines
- DAll of the above