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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.Rotary compressors are suitable for
- ALarge discharge at high pressure
- BLow discharge at high pressure
- CLarge discharge at low pressure
- DLow discharge at low pressure
2.An air compressor may be controlled by
- AThrottle control
- BClearance control
- CBlow off control
- DAny one of the above
3.The degree of reaction of an axial flow turbine is the ratio of isentropic temperature drop in a blade row to the
- AAdiabatic temperature drop in the stage
- BTotal temperature drop
- CTotal temperature drop in the stage
- DTotal adiabatic temperature drop
4.The net work input required for compressor with increase in clearance volume
- AIncreases
- BDecreases
- CRemains same
- DIncreases/decreases depending on compressor capacity
5.Volumetric efficiency of a compressor without clearance volume
- AIncreases with increase in compression ratio
- BDecreases with increase in compression ratio
- CIs not dependent upon compression ratio
- DMay increase/decrease depending on compressor capacity
6.A machine used to raise the pressure of air is called
- AGas turbine
- BI.C engine
- CCompressor
- DAir motor
7.The efficiency of jet engine is
- ALower at low speed
- BHigher at high altitudes
- CSame at all altitudes
- DHigher at high speed
8.The volume of air delivered in a medium capacity air compressor per unit time is
- A0.1 to 1.2 m³/s
- B0.15 to 5 m³/s
- CAbove 5 m³/s
- DNone of these
9.The volume of air delivered in a medium capacity air compressor per unit time is
- A0.1 to 1.2 m³/s
- B0.15 to 5 m³/s
- CAbove 5 m³/s
- DNone of these
10.The inter-cooler pressure, for minimum work required, for a two stage reciprocating air compressor, is given by (where p₁ = Intake pressure of air, p₂ = Inter-cooler pressure, and p₃ = Delivery pressure of air)
- Ap₂ = p₁ × p₃
- Bp₂ = p₁/p₃
- Cp₂ = p₁ × p₂
- Dp₂ = p₃/p₁
11.Atmospheric pressure is 1.03 kg/cm and vapour pressure is 0.03 kg/cm. The air pressure will be
- A1.03 kg/cm²
- B1.06 kg/cm²
- C1.00 kg/cm²
- D0.53 kg/cm²
12.Volumetric efficiency of a compressor with clearance volume
- AIncreases with increase in compression ratio
- BDecreases with increase in compression ratio
- CIn not dependent upon compression ratio
- DMay increase/decrease depending on compressor capacity
13.Compression efficiency is compared against
- AIdeal compression
- BAdiabatic compression
- CIsentropic compression
- DIsothermal compression
14.Phenomenon of choking in compressor means
- ANo flow of air
- BFixed mass flow rate regardless of pressure ratio
- CReducing mass flow rate with increase in pressure ratio
- DIncreased inclination of chord with air steam
15.Reheating in a multistage expansion gas turbine ________ compressor work
- AHas no effect on
- BDecreases
- CIncreases
- DNone of these
16.The work ratio of simple gas turbine cycle depends on
- APressure ratio
- BMaximum cycle temperature
- CMinimum cycle temperature
- DAll of the above
17.For perfect intercooling in a three stage compressor
- Ap₂/p₁ = p₃/p₂ = p₄/p₃
- Bp₃/p₁ = p₄/p₂
- Cp₁ p₂ = p₃ p₄
- Dp₁ p₃ = p₂ p₄
18.For perfect intercooling in a two stage compressor
- Ap₂/p₁ = p₃/p₂
- Bp₁/p₃ = p₂/p₁
- Cp₁ = p3
- Dp₁ = p₂ p3
19.The weight per horse power ratio for gas in Turbine as compared to I.C. engine and steam turbine is
- ASame
- BHigher
- CLower
- DNone of these
20.The volume of air sucked by the compressor during its suction stroke is called
- AFree air delivery
- BCompressor capacity
- CSwept volume
- DNone of these