In a four stage compressor, if the pressure at the first and third stage is 1 bar and 16 bar, then the delivery pressure at the fourth stage will be
1 bar
16 bar
64 bar
256 bar
Correct Answer :
C. 64 bar
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More
Same
More/less depending on compressor capacity
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Does not change
Increases
Decreases
First decrease and then increase
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Equal to
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More than
None of these
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More loss of air due to leakage past the cylinder
Mechanical balance is better
Air can be cooled perfectly in between
Reheating in gas turbine results in
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Decrease of thermal efficiency
Decrease of work ratio
Both (A) and (B) above
Cylinder clearance in a compressor should be
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As small as possible
About 50% of swept volume
About 100% of swept volume
Isothermal compression efficiency can be attained by running the compressor
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At very slow speed
At average speed
At zero speed
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Small quantity of air at high pressure
Small quantity of air at low pressure
Large quantity of air at low pressure
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Constant speed unloader
Relief valve
Variable speed
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Volumetric efficiency
Isothermal efficiency
Mechanical efficiency
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Passing steam over incandescent coke
Passing air and a large amount of steam over waste coal at about 65°C
Partial combustion of coal, eke, anthracite coal or charcoal in a mixed air steam blast
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Pressure slightly less than atmospheric and temperature slightly more than atmospheric
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More
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May be less or more depending upon speed
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Both (A) and (B)
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