Join Us ::

Menu Home Classes GK Engineering Past Papers Current Affairs Technical GAT Subject Programming Medical Papers

Engineering :: All Aptitude Test ::

Home » Engineering » Aptitude Test - 124
Hassan
1.In a four stroke engine, the working cycle is completed in
A. one revolution of the crankshaft
B. two revolutions of the crankshaft
C. three revolutions of the crankshaft
D. one revolution of the crankshaft
2.A nozzle is said to be a convergent nozzle
A. when the cross-section of the nozzle increases continuously from entrance to exit
B. when the cross-section of the nozzle decreases continuously from entrance to exit
C. when the cross-section of the nozzle first decreases from entrance to throat and then increases from its throat to exit
D. when the cross-section of the nozzle increases continuously from entrance to exit
3.A turbine is said to have an axial discharge when the steam leaves the blade tip at ____ to the direction of the blade motion.
A. 60°
B. 90°
C. 180°
D. 60°
4.The flow through a nozzle is regarded as
A. constant volume flow
B. constant pressure flow
C. isothermal flow
D. constant volume flow
5.The ratio of total useful heat drop to the total isentropic heat drop, is called
A. stage efficiency
B. internal efficiency
C. Rankine efficiency
D. stage efficiency
6.The discharge of steam in a convergent-divergent nozzle __________ after the throat (i.e. in the divergent portion of the nozzle)
A. remains constant
B. decreases
C. increases
D. remains constant
7.The rate of discharge through the nozzle _____ when the exit pressure is gradually reduced.
A. remains same
B. decreases
C. increases
D. remains same
8.In a nozzle, whole frictional loss is assumed to occur between
A. inlet and thoroat
B. inlet and outlet
C. throat and exit
D. inlet and thoroat
9.The critical pressure ratio for initially wet steam is
A. 0.546
B. 0.577
C. 0.582
D. 0.546
10.The isentropic enthalpy drop in moving blade is two-third of the isentropic enthalpy drop in fixed blades of a turbine. The degree of reaction will be
A. 0.4
B. 0.56
C. 0.67
D. 0.4
11.The impulse reaction turbine has its driving force
A. as an impulsive force
B. as a reaction force
C. partly as an impulsive force and partly as a reaction force
D. as an impulsive force
12.The efficiency of reaction turbine is maximum when (where ? = Angle made by the absolute velocity (V) at inlet)
A. Vb = 0.5 V cos ?
B. Vb = V cos ?
C. Vb = 0.5 V2 cos ?
D. Vb = 0.5 V cos ?
13.A regenerative steam cycle renders
A. increased work output per unit mass of steam
B. decreased work output per unit mass of steam
C. increased thermal efficiency
D. increased work output per unit mass of steam
14.De-Laval turbine is a
A. single rotor impulse turbine
B. multi-rotor impulse turbine
C. impulse reaction turbine
D. single rotor impulse turbine
15.The reheat factor is the ratio of the
A. cumulative heat drop to the isentropic heat drop
B. isentropic heat drop to the heat supplied
C. total useful heat drop to the total isentropic heat drop
D. cumulative heat drop to the isentropic heat drop
16.Thermal equilibrium means that the flow of steam is
A. isothermal
B. isentropic
C. hyperbolic
D. isothermal
17.When the back pressure of a nozzle is below the designed value of pressure at exit of nozzle, the nozzle is said to be
A. choked
B. underdamping
C. overdamping
D. choked
18.The ratio of the workdone on the blades to the energy supplied to the blades, is called
A. blading efficiency
B. nozzle efficiency
C. gross or stage efficiency
D. blading efficiency
19.The discharge is __________ at critical pressure.
A. zero
B. minimum
C. maximum
D. zero
20.The supersaturated flow of steam through a nozzle as compared to a stable flow, the available heat drop
A. remains the same
B. increases
C. decreases
D. remains the same
21.The steam leaves the nozzle at a
A. high pressure and a low velocity
B. high pressure and a high velocity
C. low pressure and a low velocity
D. high pressure and a low velocity
22.The critical pressure gives the velocity of steam at the throat
A. equal to the velocity of sound
B. less than the velocity of sound
C. more than the velocity of sound
D. equal to the velocity of sound
23.The action of steam in a steam turbine is
A. static
B. dynamic
C. static and dynamic
D. static
24.Multi-stage steam turbines are of the
A. velocity compounded type
B. reaction type
C. pressure compounded type
D. velocity compounded type
25.In reaction turbines, the axial thrust is due to
A. pressure drop across the rotor
B. change in axial velocity
C. both (a) and (b)
D. pressure drop across the rotor
26.Which of the following statement is correct?
A. The expansion of steam in a nozzle follows Rankine cycle.
B. The friction in the nozzle increases the dryness fraction of steam.
C. The pressure of steam at throat is called critical pressure.
D. The expansion of steam in a nozzle follows Rankine cycle.
27.A binary vapour plant consists of
A. steam turbine
B. steam condenser
C. mercury boiler
D. steam turbine
28.In a De-Laval nozzle expanding superheated steam from 10 bar to 0.1 bar, the pressure at the minimum cross-section (i. e. pressure at throat, p2) will be
A. 3.3 bar
B. 5.46 bar
C. 8.2 bar
D. 3.3 bar
29.The stage efficiency (?S) is given by (where ?B = Blading efficiency, and ?N = Nozzle efficiency)
A. ?S = ?B x ?N
B. ?S = ?B/?N
C. ?S = ?N/?B
D. ?S = ?B x ?N
30.The turbine blades are
A. straight
B. circular
C. curved
D. straight
Related Subjects

Date to Date Current Affairs 2022

PakMCQs.net

Quick Links

GAT Subject



   Computer Science    English Mcqs    Agriculture    

Engineering



   Computer Science    Civil Engineering    

Technical



   Networking    Electronics    Database    

Past Papers



   Model Papers    FPSC Papers    
Our Team | Career | Contact | JoinUs | Privacy Policy | DMC

© 2020-2024 by Pak-MCQs.net All Rights Reserved.

Email: [email protected]