MCQ on Compressors

1-A compressor increases the ___ of a gas by ___ its ___ .
(A) pressure, reducing, volume
(B) pressure, increasing, volume
(C) pressure, reducing, temperature
(D) pressure, increasing, temperature
2-Compressors are similar to
(A) gears
(B) flywheel
(C) pumps
(D) turbines
3-Following type is a positive displacement compressor
(A) Screw
(B) Diaphragm
(C) Centrifugal
(D) All of the above
4-Reciprocating compressors use ___ driven by a ___ .
(A) belt, pulley
(B) chain, sprocket
(C) pistons, crankshaft
(D) any of the above
5-Commonly used compressors in automotive applications
(A) 5 to 30 HP
(B) 50 to 100 HP
(C) 500 to 1000 HP
(D) more than 1000 HP
6-Reciprocating compressors suffer higher losses due to
(A) clearance volumes
(B) resistance due to discharge and suction valves
(C) more weight
(D) all of the above
7-Rotary screw compressor use __ helical screw(s) to force the gas into smaller space.
(A) one
(B) two
(C) three
(D) four
8-Screw compressors
(A) have less moving components
(B) less vibration and surging
(C) can operate at variable speeds
(D) all of the above
9-Rotary vane compressors can be
(A) either stationary or portable
(B) single or multi-staged
(C) driven be electric motors or internal combustion engines
(D) all of the above
10-Rotary vane compressors can have mechanical efficiency of about
(A) 70%
(B) 80%
(C) 90%
(D) 100%
11-A diffuser section in Centrifugal compressor coverts velocity energy to
(A) mechanical energy
(B) heat energy
(C) pressure energy
(D) potential energy
12-With multiple staging, a centrifugal compressor can achieve higher output pressure greater than
(A) 1.5 MPa
(B) 3.0 MPa
(C) 5.1 MPa
(D) 6.9 MPa
13-Compressors are used in automobiles as
(A) superchargers
(B) turbochargers
(C) both (A) and (B)
(D) pumps
14-Axial compressors use ___ to progressively compress a fluid.
(A) pistons
(B) airfoils
(C) lobes
(D) none of the above
15-Following compressor(s) is (are) used in Aeroplane engine.
(A) Axial compressor
(B) Centrifugal compressor
(C) Mixed flow compressor
(D) All of the above
ANSWERS:
1-(A), 2-(C), 3-(C), 4-(C), 5-(A), 6-(D), 7-(B), 8-(D), 9-(D), 10-(C), 11-(C), 12-(D), 13-(C), 14-(B), 15-(D)