Explore topic-wise MCQs in Mechanical Engineering Questions.

This section includes 266 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering Questions knowledge and support exam preparation. Choose a topic below to get started.

101.

The resistance offered to the flow of fluid inside a piston develops into
A. pressure
B. force
C. stress
D. all of the above
Answer» B. force
Discussion
102.

Which of the following statements are false? 1. Pressure is resistance to flow 2. Friction creates pressure 3. Load cannot create pressure on the system 4. The pressure developed decreases if load offers more resistance
A. 1, 2 and 4
B. 1 and 2
C. 3 and 4
D. none of the above
Answer» D. none of the above
Discussion
103.

Guide angle as per the aerofoil theory of Kaplan turbine blade design is defined as the angle between_________________?
A. lift and resultant force
B. drag and resultant force
C. lift and tangential force
D. lift and drag
E. resultant force and tangential force
Answer» B. drag and resultant force
Discussion
104.

A turbine pump is basically a centrifugal pump equipped additionally with_________________?
A. adjustable blades
B. backward curved blades
C. vaned diffusion casing
D. inlet guide blades
E. totally submerged operation facility
Answer» D. inlet guide blades
Discussion
105.

In reaction turbine, draft tube is used_____________________?
A. to transport water downstream without eddies
B. to convert the kinetic energy to flow energy by a gradual expansion of the flow cross-section
C. for safety of turbine
D. to increase flow rate
E. none of the above
Answer» C. for safety of turbine
Discussion
106.

Which place in hydraulic turbine is most susceptible for cavitation __________________?
A. inlet of draft rube
B. blade inlet
C. guide blade
D. penstock
E. draft tube exit
Answer» B. blade inlet
Discussion
107.

Hydraulic accumulator is used for____________________?
A. accumulating oil
B. supplying large quantities of oil for very short duration
C. generally high pressures to operate hydraulic machines
D. supplying energy when main supply fails
E. accumulating hydraulic energy
Answer» E. accumulating hydraulic energy
Discussion
108.

The specific speed of turbine is defined as the speed of a unit___________________?
A. of such a size that it delivers unit dis-charge at unit head
B. of such a size that it delivers unit dis-charge at unit power
C. of such a size that it requires unit power per unit head
D. of such a size that it produces unit horse power with unit head
E. none of the above
Answer» E. none of the above
Discussion
109.

Francis turbine is best suited for_____________________?
A. medium head application from 24 to 180 m
B. low head installation up to 30 m
C. high head installation above 180 m
D. all types of heads
E. none of the above
Answer» B. low head installation up to 30 m
Discussion
110.

Specific speed for reaction turbines ranges from___________________?
A. 0 to 4.5
B. 10 to 100
C. 80 to 200
D. 250 to 300
E. none of the above
Answer» C. 80 to 200
Discussion
111.

For small discharge at high pressure, following pump is preferred_____________________?
A. centrifugal
B. axial flow
C. mixed flow
D. propeller
E. reciprocating
Answer» F.
Discussion
112.

The discharge through a reaction turbine with increase in unit speed____________________?
A. increases
B. decreases
C. remains unaffected
D. first increases and then decreases
E. first decreases and then increases
Answer» C. remains unaffected
Discussion
113.

Francis, Kaplan and propeller turbines fall under the category of___________________?
A. Impulse turbines
B. Reaction turbines
C. Axial flow turbines
D. Mixed flow turbines
E. Reaction-cum-impulse turbines
Answer» C. Axial flow turbines
Discussion
114.

The horse power required in above case will be___________________?
A. same
B. 0.75 B.H.P.
C. B.H.P./0.75
D. 1.5 B.H.P.
E. none of the above
Answer» C. B.H.P./0.75
Discussion
115.

The maximum number of jets generally employed in impulse turbine without jet interference is________________?
A. 4
B. 6
C. 8
D. 12
E. 16
Answer» C. 8
Discussion
116.

High specific speed of turbine implies it is__________________?
A. propeller turbine
B. Francis turbine
C. impulse turbine
D. any one of the above
E. none of the above
Answer» B. Francis turbine
Discussion
117.

Medium specific speed of a pump implies it is_________________?
A. centrifugal pump
B. mixed flow pump
C. axial flow pump
D. any one of the above
E. none of the above
Answer» C. axial flow pump
Discussion
118.

Motion of a liquid in a volute casing of a centrifugal pump is an example of____________________?
A. rotational flow
B. radial
C. forced spiral vortex flow
D. forced cylindrical vortex flow
E. spiral vortex flow
Answer» F.
Discussion
119.

Any change in load is adjusted by adjusting following parameter on turbine______________?
A. net head
B. absolute velocity
C. blade velocity
D. flow
E. relative velocity of flow at inlet
Answer» E. relative velocity of flow at inlet
Discussion
120.

Indicator diagram of a reciprocating pump is a graph between________________?
A. flow vs swept volume
B. pressure in cylinder vs swept volume
C. flow vs speed
D. pressure vs speed
E. swept volume vs speed
Answer» C. flow vs speed
Discussion
121.

The angle of taper on draft tube is A. greater than 15° B. greater than 8° C. greater than 5° D. less than 8° E. less than 3°.___________________?
The angle of taper on draft tube is
A. greater than 15°
B. greater than 8°
C. greater than 5°
D. less than 8°
E. less than 3°.
Answer» E. less than 3°.
Discussion
122.

Reaction turbines are used for____________________?
A. low head
B. high head
C. high head and low discharge
D. high head and high discharge
E. low head and high discharge
Answer» F.
Discussion
123.

Casting of a centrifugal pump is designed so as to minimize________________?
A. friction loss
B. cavitation
C. static head
D. loss of kinetic energy
E. starting time
Answer» E. starting time
Discussion
124.

Low-torque high-speed motors are used in
A. cranes
B. winches
C. fans
D. all of the above
Answer» D. all of the above
Discussion
125.

In axial flow fans and turbines, fluid enters and leaves as follows________________?
A. radially, axially
B. axially, radially
C. axially, axially
D. radially, radially
E. combination of axial and radial
Answer» D. radially, radially
Discussion
126.

The flow rate in gear pump___________________?
A. increases with increase in pressure
B. decreases with increase in pressure
C. more or less remains constant with in-crease in pressure
D. unpredictable
E. none of the above
Answer» D. unpredictable
Discussion
127.

Air vessels in reciprocating pump are used to__________________?
A. smoothen flow
B. reduce acceleration to minimum
C. increase pump efficiency
D. save pump from cavitation
E. increase pump head
Answer» C. increase pump efficiency
Discussion
128.

Maximum impulse will be developed in hydraulic ram when ___________________?
A. waste valve closes suddenly
B. supply pipe is long
C. supply pipe is short
D. ram chamber is large
E. supply pipe has critical diameter
Answer» B. supply pipe is long
Discussion
129.

A hydraulic intensifier normally consists of __________________?
A. two cylinders, two rams and a storage device
B. a cylinder and a ram
C. two co-axial rams and two cylinders
D. a cylinder, a piston, storage tank and control valve
E. special type of pump with storage device and a pressure regulator
Answer» D. a cylinder, a piston, storage tank and control valve
Discussion
130.

What is the relation between pressure and overall efficiency for a gear pump?
A. as pressure increases, overall efficiency decreases
B. as pressure increases, overall efficiency increases
C. overall efficiency is not affected by change in pressure
D. cannot say
Answer» B. as pressure increases, overall efficiency increases
Discussion
131.

Head developed by a centrifugal pump depends on___________________?
A. impeller diameter
B. speed
C. fluid density
D. type of casing
E. A. and B. above
Answer» F.
Discussion
132.

The efficiency of a centrifugal pump is maximum when its blades are__________________?
A. straight
B. bent forward
C. bent backward
D. bent forward first and then backward
E. bent backward first and then forward
Answer» D. bent forward first and then backward
Discussion
133.

Which of the following statements are true? 1. the length of two stage telescopic cylinder is more than a standard cylinder 2. the length of two stage telescopic cylinder is less than a standard cylinder 3. telescopic cylinder is single acting 4. telescopic cylinder is double acting
A. 1 and 3
B. 2 and 3
C. 2, 3 and 4
D. 1, 3 and 4
Answer» D. 1, 3 and 4
Discussion
134.

Reciprocating pumps are no more to be seen in industrial applications (in comparison to centrifugal pumps) because of____________________?
A. high initial and maintenance cost
B. lower discharge
C. lower speed of operation
D. necessity of air vessel
E. all of the above
Answer» B. lower discharge
Discussion
135.

Which of the following statements is true for standard hydraulic cylinder and a telescopic cylinder?
A. telescopic and standard cylinders give same stroke length
B. telescopic cylinders give lesser stroke length than standard cylinder
C. telescopic cylinders give greater stroke length than standard cylinder
D. none of the above
Answer» D. none of the above
Discussion
136.

Telescopic cylinders have
A. only two stage units
B. only three stage units
C. two or three stage units
D. multistage units
Answer» E.
Discussion
137.

Variable displacement pumps used in hydraulic applications can 1. have variable flow rate 2. consume less energy 3. be operated with high accuracy for slow and rapid motion 4. generate more heat
A. 1 and 2
B. 3 and 4
C. 1, 2 and 3
D. all of the above
Answer» D. all of the above
Discussion
138.

Which type of displacement is observed in gear pumps?
A. only variable displacement
B. only fixed displacement
C. both fixed and variable displacement
D. none of the above
Answer» C. both fixed and variable displacement
Discussion
139.

What is the advantage of internal gear pump?
A. moderate speed
B. medium pressure
C. high viscosity fluids can be used
D. all of the above
Answer» D. all of the above
Discussion
140.

What is the principle of operation used in gear pumps?
A. two gears rotate in same direction
B. two gears rotate in opposite direction
C. both a. and b.
D. none of the above
Answer» C. both a. and b.
Discussion
141.

Which flow pattern gets affected when cross section of the pipe is changed?
A. laminar flow
B. turbulent flow
C. laminar and turbulent
D. none of the above
Answer» C. laminar and turbulent
Discussion
142.

How does cushioning affect the speed of the piston when the cylinder is cushioned at extreme end?
A. cushioning decreases the speed of piston near the extreme ends of the cylinder
B. cushioning increases the speed of piston near the extreme ends of the cylinder
C. cushioning increases the speed of piston at the beginning of the stroke in the cylinder
D. cushioning decreases the speed of piston at the beginning of the stroke in the cylinder
Answer» B. cushioning increases the speed of piston near the extreme ends of the cylinder
Discussion
143.

The rotation of which inner element causes the liquid to pump out in centrifugal pumps?
A. internal gear
B. rotation of the impeller
C. cylinder rotor
D. none of the above
Answer» C. cylinder rotor
Discussion
144.

The Reynolds number for laminar flow is
A. more than 2800
B. more than 2000
C. less than 2000
D. between 2000 and 2800.
Answer» D. between 2000 and 2800.
Discussion
145.

What is the characteristic of turbulent flow?
A. high velocity
B. the direction of flow and movement of particles is same
C. change in cross section does not affect the flow
D. all of the above
Answer» B. the direction of flow and movement of particles is same
Discussion
146.

What is the DC range of of solenoids in pneumatic systems?
A. 12 V and 24 V
B. 110 V and 220 V
C. both a. and b.
D. none of the above
Answer» B. 110 V and 220 V
Discussion
147.

Which of the following statements is/are true according to Bernoulli's principle? 1. If a system has constant flow rate, change in cross-section area of the pipe affects the total energy of system 2. The change in cross-section has no effect on the total energy of the system and is constant if it has varying flow rate 3. A system has constant total energy, if flow rate is constant and change in cross-section has no effect on total energy
A. Statement 1
B. Statement 2
C. Statement 3
D. all of the above
Answer» D. all of the above
Discussion
148.

Speed of the actuator is affected by
A. cross-section area of the orifice
B. velocity of flow
C. pipe diameter
D. all of the above
Answer» E.
Discussion
149.

Which of the following is used an output device on a ladder diagram?
A. proximity sensor
B. detent switch
C. relay
D. all of the above
Answer» D. all of the above
Discussion
150.

How is strong magnetic field in a solenoid achieved?
A. strong magnetic field in a solenoid is achieved, if coil acts as conductor
B. coil is surrounded by a iron frame
C. iron core is placed at the centre of the coil
D. all of the above
Answer» E.
Discussion