Compressors, Gas Turbines and Jet Engines MCQs

Question 1

In a double acting compressor, the air is compressed

Accepted Answer

In a single cylinder on both sides of the piston

Answer

In one cylinder

Answer

In two cylinders

Answer

In two cylinders on both sides of the piston

Question 2

The work-done on a compressor will be minimum if air is taken from

Accepted Answer

A source of low temperature air

Answer

The atmosphere

Answer

A source at 0° C

Answer

A source of high temperature air

Question 3

Free air is the air at

Accepted Answer

Atmospheric conditions at any specific location

Answer

20°C and 1 kg/cm2 and relative humidity of 36%

Answer

0°C and standard atmospheric conditions

Answer

15°C and 1 kg/cm2

Question 4

Standard air is the air at

Accepted Answer

20°C and 1 kg/cm2 and relative humidity 36%

Answer

Atmospheric conditions at any specific location

Answer

0°C and standard atmospheric conditions

Answer

15°C and 1 kg/cm2

Question 5

The overall efficiency of the compressed air system is the

Accepted Answer

Ratio of shaft output of the air motor to the shaft input to the compressor

Answer

Ratio of shaft input to the compressor to the shaft output of air motor

Answer

Product of shaft output of air motor and shaft input to the compressor

Answer

None of the above

Question 6

In a jet engine, the air-fuel ratio is

Accepted Answer

60 : 1

Answer

30 : 1

Answer

40 : 1

Answer

50 : 1

Question 7

The reason for volumetric efficiency of reciprocating compressor being less than 100 percent is

Accepted Answer

All of these

Answer

Pressure drop across the valves

Answer

Superheating in compressor

Answer

Clearance volume and leakages

Question 8

Turbofan engine employs

Accepted Answer

Two or more air streams

Answer

One air stream

Answer

No air stream

Answer

Solid fuel firing

Question 9

Gas turbines for power generation are normally used

Accepted Answer

To supply peak load requirements

Answer

To supply base load requirements

Answer

To enable start thermal power plant

Answer

In emergency