The laminar/viscous flow is characterized by Reynolds number which is
A.
less than the critical value
B.
Equal to critical value
C.
More than critical value
D.
None of the above.
Answer»
A. less than the critical value
102.
The laminar flow is characterized by
A.
Existence of eddies
B.
Irregular motion of fluid particles
C.
Fluid particles moving in layers parallel to the boundary surface
D.
None of the above.
Answer»
C. Fluid particles moving in layers parallel to the boundary surface
103.
In case of laminar flow, the loss of pressure head is proportional to
A.
Velocity
B.
Velocity2
C.
Velocity3
D.
None of the above.
Answer»
A. Velocity
104.
The pressure gradient in the direction of flow is equal to the shear gradient in the direction
A.
Parallel to the direction of flow
B.
Normal to the direction of flow
C.
Either of the above
D.
None of the above.
Answer»
B. Normal to the direction of flow
105.
…... studied the laminar flow through a circular tube experimentally
A.
Prandtl
B.
Pascal
C.
Hagen and Poiseuille
D.
None of the above.
Answer»
C. Hagen and Poiseuille
106.
…... is the most commonly used equation for the velocity distribution for laminar flow through pipes.
A.
u = umax [1 – (r/R)]
B.
u = umax [1- (r/R)2]
C.
u = umax [1 – (r/R)3]
D.
u = u2max [1 – (r/R)2]
Answer»
B. u = umax [1- (r/R)2]
107.
In laminar flow the pressure drop per unit length of pipe (∆p/L) is given as
A.
32𝜇͞u/D2
B.
2𝜇͞u/D2
C.
32𝜇͞u/D3
D.
None of above.
Answer»
A. 32𝜇͞u/D2
108.
The K.E. correction factor a for a circular pipe is equal to
A.
2
B.
3
C.
4
D.
6.
Answer»
A. 2
109.
The momentum correction factor b for a circular pipe is to equal to
A.
1/3
B.
2/3
C.
4/3
D.
5/3
Answer»
C. 4/3
110.
For viscous flow the co-efficient of friction is given by
A.
f = 8/Re
B.
f = 16/Re
C.
f = 32/Re
D.
f = 60/Re.
Answer»
B. f = 16/Re
111.
In case of viscous flow through circular pipes
A.
͞u = 2 umax
B.
u = (3/2) umax
C.
u = umax/2
D.
none of the above.
Answer»
B. u = (3/2) umax
112.
The maximum velocity in a circular pipe when flow is laminar occurs at
A.
The top of the pipe
B.
The bottom of the pipe
C.
The centre of the pipe
D.
Not necessarily at the centre.
Answer»
C. The centre of the pipe
113.
The flow is said to be turbulent when Reynolds number is
A.
Less than 1000
B.
Equal to 2000
C.
Greater than 4000
D.
Between 1000 to 4000.
Answer»
C. Greater than 4000
114.
The shear in turbulent flow is mainly due to
A.
Heat transfer
B.
Mass transfer
C.
Momentum transfer
D.
All of the above.
Answer»
C. Momentum transfer
115.
Which of the following statements is correct? Wall turbulence occurs
A.
In immediate vicinity of solid surfaces and in the boundary layer flows where the fluid has a negligible mean acceleration
B.
In jets, wakes, mixing layer etc.
C.
Where there is conversion of potential energy into kinetic energy by the process of mixing
D.
None of the above.
Answer»
A. In immediate vicinity of solid surfaces and in the boundary layer flows where the fluid has a negligible mean acceleration
116.
The flow in town water supply pipes is generally
A.
Laminar
B.
Turbulent
C.
Transition
D.
Any of the above.
Answer»
B. Turbulent
117.
The most essential feature of a turbulent flow is
A.
High velocity
B.
Velocity at a point remains constant with time
C.
Large discharge
D.
Velocity and pressure at a point exhibit irregular fluctuations of high frequency.
Answer»
D. Velocity and pressure at a point exhibit irregular fluctuations of high frequency.
118.
In turbulent flow the velocity distribution is a function of the distance y measured from the boundary surface and shear friction velocity uf, and follows a
A.
Linear law
B.
Hyperbolic law
C.
Parabolic law
D.
Logarithmic law.
Answer»
D. Logarithmic law.
119.
A turbulent flow is considered steady when
A.
The algebraic sum of velocity fluctuations is zero
B.
The velocity at a point does not change with Time
C.
Temporal mean velocity at a point remains constant with time
D.
The discharge remains constant.
Answer»
C. Temporal mean velocity at a point remains constant with time
120.
The Darcy-Weisbach friction factor f which is a direct measure of resistance to flow in pipes depends on which of the following?
A.
Relative roughness, velocity and viscosity
B.
Relative roughness, diameter and viscosity
C.
Roughness height, diameter and velocity
D.
Roughness height, diameter, velocity and kinematic viscosity.
Answer»
D. Roughness height, diameter, velocity and kinematic viscosity.
121.
Commercial cast-iron and steel pipes carrying fluids under pressure are regarded as hydraulically smooth when
A.
The laminar layer is thin as compared to the average height of roughness elements
B.
The height of the roughness projections is low
C.
The roughness elements are all completely covered by the laminar sublayer
D.
None of the above.
Answer»
C. The roughness elements are all completely covered by the laminar sublayer
122.
Intensity of turbulence is
A.
The average K.E. of turbulence
B.
The violence of turbulent fluctuations and is measured by the root mean square value of velocity fluctuations
C.
The mean time interval between the reversals in the sign of velocity fluctuation
D.
None of the above.
Answer»
B. The violence of turbulent fluctuations and is measured by the root mean square value of velocity fluctuations
123.
Which of the following factors determine the friction factor for turbulent flow in a rough pipe?
A.
Mach number and relative roughness
B.
Froude’s number and Mach’s number
C.
Reynolds number and relative roughness
D.
Froude’s number and relative roughness.
Answer»
C. Reynolds number and relative roughness
124.
In case of turbulent flow of a fluid through a circular tube (as compared to the case of laminar flow at the same flow rate) the maximum velocity is ....., shear stress at the wall is ....., and the pressure drop across a given length is ....., the correct words for the blanks are, respectively
A.
lower, higher, lower
B.
lower, higher, higher
C.
higher, lower, lower
D.
higher, higher, higher
Answer»
B. lower, higher, higher
Chapter: Flow through pipes
125.
In a laminar flow, Reynold’s number is
A.
Less than 2000
B.
More than 2000
C.
More than 2000 but less than 4000
D.
None of the above.
Answer»
A. Less than 2000
126.
In a turbulent flow, Reynold’s number is
A.
Less than 4000
B.
More than 4000
C.
Between 2000 and 4000
D.
None of the above.
Answer»
B. More than 4000
127.
In case of a laminar flow, the loss of pressure head is
A.
Proportional to (velocity)2
B.
Proportional to velocity
C.
Proportional to (velocity)1/2
D.
None of the above.
Answer»
B. Proportional to velocity
128.
In case of a turbulent flow, the loss of head is approximately proportional to
A.
Velocity
B.
(Velocity) ^1/2
C.
(Velocity) ^3/4
D.
(Velocity) ^2
Answer»
D. (Velocity) ^2
129.
Darcy-Weisbach equation is used to find loss of head due to :
A.
Sudden enlargement
B.
Sudden contraction
C.
Friction
D.
None of the above.
Answer»
C. Friction
130.
Chezy’s formula is given as
A.
V = C √𝑚2 i
B.
V = C2 √𝑚𝑖2
C.
V = C√𝑚𝑖
D.
V = C √𝑚2𝑖3
Answer»
C. V = C√𝑚𝑖
131.
Loss of head due to sudden enlargement is given as
A.
(𝑉1−𝑉2)32𝑔
B.
(𝑉1−𝑉2)22𝑔
C.
(𝑉12−𝑉22)2𝑔
D.
√(𝑉1−𝑉2)2𝑔
Answer»
B. (𝑉1−𝑉2)22𝑔
132.
2𝑔
148. The power transmitted through the pipe is maximum when head lost due to friction in the pipe is equal to
A.
(1/3) rd of the total supply head
B.
(1/4) th of the total supply head
C.
(1/5) th of the total supply head
D.
(1/8) th of the total supply head
Answer»
C. (1/5) th of the total supply head
133.
The energy loss in a pipeline is due to
A.
Surface roughness only
B.
Viscous action only
C.
Friction offered by pipe wall as well as by viscous function
D.
None of the above.
Answer»
C. Friction offered by pipe wall as well as by viscous function
134.
In a pipe flow the minor losses are those
A.
Which depend on the length of the pipeline
B.
Caused by friction and are thus also called friction losses.
C.
Which have a small magnitude
D.
Which are caused on account of total disturbance produced by such fittings as valves, bends, etc.
Answer»
D. Which are caused on account of total disturbance produced by such fittings as valves, bends, etc.
135.
In flow through pipe bends the pressures on inner and out radii
A.
Stand at the same level increasing gradually towards the pipe center.
B.
Vary, it being more on the inner core.
C.
Are different, pressure increases with increase in radius and is, therefore, more at the outer radius.
D.
Do not vary and are the same as at the center of the pipe.
Answer»
D. Do not vary and are the same as at the center of the pipe.
136.
The condition for maximum transmission of power through a pipeline is that one-third of the available
head must be consumed in friction. The corresponding efficiency of the pipeline is
A.
33·3%
B.
66·67%
C.
90%
D.
100%.
Answer»
B. 66·67%
137.
For achieving continuous flow through a system, no position of the pipe should be higher than
A.
20 m
B.
6 m
C.
7·6 m
D.
10 m.
Answer»
C. 7·6 m
138.
For turbulent flow in smooth pipes, the entrance length is taken as
A.
20
B.
50
C.
80
D.
115.
Answer»
B. 50
139.
The entrance length or length of establishment of flow is
A.
The length in which the boundary layer remains uniform
B.
The pipe length inside the reservoir
C.
The length of pipe from its entrance in which the flow may be assumed irrotational
D.
The initial length in which the flow develops fully such that the velocity profile does not change downstream.
Answer»
D. The initial length in which the flow develops fully such that the velocity profile does not change downstream.
140.
Due to which of the following phenomena water hammer is caused?
A.
Incompressibility of fluid
B.
Sudden opening of a valve in a pipeline
C.
The material of the pipe being elastic
D.
Sudden closure (partial or complete) of a valve in pipe flow.
Answer»
D. Sudden closure (partial or complete) of a valve in pipe flow.
141.
Under which of the following conditions the closure of valve is considered rapid? (where L = length of pipe, C = velocity of pressure wave produced due to water hammer.)
A.
The duration of valve closure is greater than 2L/C
B.
The duration of valve closure is less than L/C
C.
The duration of valve closure is less than 2L/C
D.
None of the above.
Answer»
C. The duration of valve closure is less than 2L/C
Chapter: Impact of Jet and Hydraulic Turbines
142.
The force exerted by a jet of water on a moving vertical plate, in the direction of motion of plate is given by
A.
ρaV2
B.
ρaV3
C.
ρa (V – u)2
D.
ρa (V – u)3
Answer»
C. ρa (V – u)2
143.
When a steady jet impinges on a fixed inclined surface
A.
The flow is divided into parts proportional to the angle of inclination of the surface
B.
No force is exerted by the jet on the vane
C.
The momentum component is unchanged parallel to the surface
D.
None of the above.
Answer»
A. The flow is divided into parts proportional to the angle of inclination of the surface
144.
For maximum efficiency of a series of curved vanes, the speed is
A.
Equal to the jet speed
B.
3/4 of the jet speed
C.
1/2 of the jet speed
D.
1/3 of the jet speed.
Answer»
C. 1/2 of the jet speed
145.
The efficiency of jet propulsion with inlet orifices at right angles to the direction of motion of ship is
given by
A.
2u/ (V + u)
B.
2V/ (V + u) 2
C.
2Vu/ (V + u) 2
D.
2u (V-u)/V3
Answer»
B. 2V/ (V + u) 2
146.
For an impulse turbine which of the following statements is correct :
A.
It makes use of a draft tube
B.
It is not exposed to atmosphere
C.
It is most suited for low head installations
D.
It operates with initial complete conversion of pressure head to velocity head.
Answer»
D. It operates with initial complete conversion of pressure head to velocity head.
147.
Which of the following statements is correct in case of a Pelton wheel :
A.
It can operate at optimum efficiency at all high speeds
B.
It is kept entirely submerged in water below the tail race.
C.
It gives optimum efficiency at runaway speed
D.
It operates by converting the available energy fully into kinetic energy before entering the rotor.
Answer»
D. It operates by converting the available energy fully into kinetic energy before entering the rotor.
148.
The effective (or net) head at the turbine is
A.
The sum of gross head plus head loss in penstock and the velocity head at the turbine exit.
B.
The difference between gross head minus the head loss in penstock
C.
The difference between the gross head minus head loss in penstock and the velocity head at the turbine exit
D.
The sum of gross head plus the head loss in the penstock.
Answer»
C. The difference between the gross head minus head loss in penstock and the velocity head at the turbine exit
149.
The difference between the power obtained from the turbine shaft and power supplied by water at its entry to the turbine is equal to
A.
Sum of hydraulic and mechanical losses
B.
Sum of mechanical and volumetric losses
C.
Mechanical losses
D.
Hydraulic losses.
Answer»
A. Sum of hydraulic and mechanical losses
150.
Which of the following statements is a definition of the hydraulic efficiency of a turbine?
A.
The ratio of power available at the turbine shaft to that supplied to it by runner.
B.
The ratio of the power supplied by the runner to the power available at the shaft.
C.
The ratio of power utilized by runner to that supplied by the water at entry to the turbine.
D.
The ratio of power supplied by water at entry to the power utilized by runner.
Answer»
C. The ratio of power utilized by runner to that supplied by the water at entry to the turbine.
151.
The power which appears in the expression for the specific speed is the:
A.
Shaft power
B.
Water power
C.
Power into the turbine
D.
None of the above.
Answer»
A. Shaft power
152.
Which of the following statements is correct: Runaway speed of a hydraulic turbine is the speed
A.
At which there would be no damage to the turbine runner
B.
At which the turbine runner can be allowed to run freely without load and with wicket gates wide open
C.
Corresponding to maximum overload permissible
D.
At full load.
Answer»
B. At which the turbine runner can be allowed to run freely without load and with wicket gates wide open
153.
Which of the following statements is correct for a reaction turbine?
A.
The outlet must be above the tail race.
B.
Water may be allowed to enter a part or whole of wheel circumference.
C.
Flow can be regulated without loss.
D.
There is only partial conversion of available head to velocity head before entry to rotor.
Answer»
D. There is only partial conversion of available head to velocity head before entry to rotor.
154.
In a reaction turbine the function of a draft tube is to
A.
Provide safety to turbine
B.
Prevent air from entering
C.
Reconvert the kinetic energy to flow energy
D.
Increase the rate of flow
Answer»
C. Reconvert the kinetic energy to flow energy
155.
Which of the following statements with respect to a reaction water turbine is incorrect:
A.
The spiral casing serves to uniformly distribute water into guide blades
B.
The water leaves the turbine at atmospheric pressure
C.
The draft tube allows setting of the turbine above the tail race with minimum reduction of available energy
D.
The guide vanes direct the flow at proper angle.
Answer»
B. The water leaves the turbine at atmospheric pressure
156.
Which of the following turbines is suitable for specific speed ranging from 300 to 1000 and heads below 30 m:
A.
Francis
B.
Kaplan
C.
Propeller
D.
Pelton.
Answer»
B. Kaplan
157.
Specific speed of a turbo-machine
A.
Relates the shape rather than the size of the machine
B.
Remains unchanged under different condi tions of operation
C.
Has the dimensions of rotational speed
D.
Is the speed of a machine having unit dimensions.
Answer»
A. Relates the shape rather than the size of the machine
158.
In an outward radial flow turbine energy conversion process is
A.
Purely by reaction only
B.
Purely by impulse only
C.
Partly by impulse and partly by reaction
D.
None of the above.
Answer»
D. None of the above.
159.
Which of the following turbines is least efficient under part load conditions:
A.
Propeller
B.
Kaplan
C.
Francis
D.
Pelton.
Answer»
A. Propeller
160.
A surge tank is used to
A.
Prevent occurrence of hydraulic jump
B.
Smoothen the flow
C.
Relieve the pipeline of excessive pressure transients
D.
Avoid reversal of flow.
Answer»
C. Relieve the pipeline of excessive pressure transients
161.
Which of the following turbines is most efficient at partload operation?
A.
Kaplan
B.
Propeller
C.
Francis
D.
Pelton wheel.
Answer»
A. Kaplan
162.
With respect to a Kaplan turbine which of the following statements is incorrect?
A.
It employs large guide vane angles than is the case for a Francis turbine.
B.
It is designed for flow velocity of mixed flow type.
C.
It has blades of small camber to prevent separation.
D.
It can adjust both guide vane and blade angles according to rate of discharge.
Answer»
B. It is designed for flow velocity of mixed flow type.
163.
Specific speed of an impulse turbine (Pelton wheel) ranges from
A.
12 to 70
B.
80 to 400
C.
300 to 1000
D.
1000 to 1200.
Answer»
A. 12 to 70
164.
Cavitation damage in turbine runner occurs near the
A.
Inlet on the convex side of blades
B.
Outlet on the convex side of blades
C.
Inlet on the concave side of blades
D.
Outlet on the concave side of blades.
Answer»
B. Outlet on the convex side of blades
165.
Which of the following serious problems arise from cavitation?
A.
Noise and vibration.
B.
Damage to blade surface.
C.
Fall in efficiency.
D.
All of the above.
Answer»
D. All of the above.
166.
A Kaplan turbine is
A.
An inward flow impulse turbine
B.
Low head axial flow turbine
C.
High head axial flow turbine
D.
High head mixed flow turbine.
Answer»
B. Low head axial flow turbine
167.
An impulse turbine requires
A.
High head and small quantity of flow
B.
Low head and small quantity of flow
C.
Low head and high rate of flow
D.
None of the above
Answer»
A. High head and small quantity of flow
168.
......of a turbine is defined as the ratio of power available at the turbine shaft to the power supplied by the water jet.
A.
Mechanical efficiency
B.
Hydraulic efficiency
C.
Overall efficiency
D.
Volumetric efficiency.
Answer»
C. Overall efficiency
169.
The ratio of power developed by the runner to the power supplied by the jet at entrance to the turbine is
known as
A.
Hydraulic efficiency
B.
Mechanical efficiency
C.
Volumetric efficiency
D.
Overall efficiency.
Answer»
A. Hydraulic efficiency
170.
The water which acts on the runner blades of a reaction turbine is under a pressure
A.
Equal to atmospheric
B.
Below atmospheric
C.
Above atmospheric
D.
None of the above.
Answer»
C. Above atmospheric
171.
The runner passages of a reaction turbine are
A.
Partially filled with water
B.
Always completely filled with water
C.
Never filled with water
D.
None of the above.
Answer»
B. Always completely filled with water
172.
The value of speed ratio (Ku) in case of a Francis turbine ranges from
A.
0.2 to 0.3
B.
0.4 to 0.5
C.
0.6 to 0.9
D.
None of the above.
Answer»
C. 0.6 to 0.9
173.
The value of flow ratio (Kf) in case of a Francis turbine varies from:
A.
0.1 to 0.14
B.
0.15 to 0.30
C.
0.35 to 0.5
D.
0.6 to 0.9.
Answer»
B. 0.15 to 0.30
174.
A Kaplan turbine claims which of the following advantages over a Francis turbine?
A.
More compact in construction and smaller in size.
B.
Partload efficiency is considerably high.
C.
Low frictional losses.
D.
All of the above.
Answer»
D. All of the above.
175.
Which of the following draft tubes is suited particularly for helical flow?
A.
Conical type draft tube.
B.
Elbow type draft tube.
C.
Moody’s spreading draft tube.
D.
None of the above.
Answer»
C. Moody’s spreading draft tube.
176.
Which of the following surge tank is also called a throttled surge tank?
A.
Inclined surge tank.
B.
Expansion chamber surge tank.
C.
Restricted orifice surge tank.
D.
None of the above
Answer»
C. Restricted orifice surge tank.
Chapter: Centrifugal Pumps
177.
Which of the following types of impeller is used for centrifugal pumps dealing with muds?
A.
One-side shrouded
B.
Two -sides shrouded
C.
Double section
D.
Open.
Answer»
D. Open.
178.
Which of the following statements is correct with reference to an impeller with backward curved vanes?
A.
It has a falling head - discharge characteristic.
B.
It has rising head - discharge characteristic
C.
It is easier to fabricate.
D.
It cannot run at speeds other than the design speed.
Answer»
A. It has a falling head - discharge characteristic.
179.
The head developed by a centrifugal pump may be expressed as
A.
H = (Vw2 u2 + Vw1 u2)/g
B.
H = Vw2 u2 /g
C.
H = Vw1 u1 /g
D.
None of the above.
Answer»
B. H = Vw2 u2 /g
180.
With reference to a centrifugal pump which of the following statements is incorrect?
A.
The discharge control valve is fitted in the delivery pipe.
B.
The suction pipe is provided with a foot valve and a strainer.
C.
The suction pipe has larger diameter as compared to the discharge pipe.
D.
The discharge control valve is fitted in the suction pipe.
Answer»
D. The discharge control valve is fitted in the suction pipe.
181.
A centrifugal pump should be so installed above the water level in the sump such that
A.
The negative pressures are not allowed to develop in the impeller
B.
The negative pressures do not reach as low a value as the vapour pressure
C.
Its height is more than 10·28 m at ordinary temperature of liquid
D.
None of the above.
Answer»
B. The negative pressures do not reach as low a value as the vapour pressure
182.
The specific speed of a pump is defined as the speed of unit of such a size that it
A.
Produces unit power with unit head available
B.
Delivers unit discharge at unit head
C.
Requires unit power to develop unit head
D.
Delivers unit discharge at unit power.
Answer»
B. Delivers unit discharge at unit head
183.
Which of the following statements pertaining to a given centrifugal pump is correct?
A.
Discharge varies as the square of speed
B.
Power varies as the square of speed
C.
Discharge varies directly as speed
D.
Head varies inversely as speed.
Answer»
C. Discharge varies directly as speed
184.
The delivery valve, while starting centrifugal pump, is kept
A.
Fully closed
B.
Fully open
C.
Half open
D.
In any position.
Answer»
A. Fully closed
185.
Which of the following is not a dimensionless parameter?
A.
Friction factor
B.
Specific speed
C.
Thoma’s cavitation parameter
D.
Pressure co-efficient.
Answer»
B. Specific speed
186.
With reference to manometric head which of the following statements is correct?
A.
It is the head developed by the pump.
B.
It is the height to which water is lifted by the pump measured above the pump centreline.
C.
it is the difference in elevation between the water surface in the high level reservoir and the water level in the sump.
D.
It is the difference in the piezometric heads between the points on the delivery and suction pipes as close to the pump as possible.
Answer»
D. It is the difference in the piezometric heads between the points on the delivery and suction pipes as close to the pump as possible.
187.
Higher specific speeds (160 to 500) of centrifugal pump indicate that the pump is of
A.
Radial flow type
B.
Axial flow type
C.
Mixed flow type
D.
Any of these types.
Answer»
B. Axial flow type
188.
What will happen if requirements of net positive suction head (NPSH) for a given pump are not satisfied?
A.
The pump will get cavitated.
B.
The pump will consume more power.
C.
The pump will not develop he
Answer»
A. The pump will get cavitated.
189.
In centrifugal pumps, cavitation is reduced by
A.
Increasing the flow velocity
B.
Reducing the discharge
C.
Throttling the discharge
D.
Reducing the suction head.
Answer»
D. Reducing the suction head.
190.
Which of the following statements pertaining to a centrifugal pump is incorrect?
A.
The suction lift of a pump can be upto 10·3 m or even more.
B.
The impellers of a multi-stage pump are arranged in parallel to discharge a large quantity of liquid.
C.
The volute casing of the pump maintains the velocity of flow constant, prevents eddies and converts velocity head to pressure he
Answer»
A. The suction lift of a pump can be upto 10·3 m or even more.
191.
Regarding cavitation which of the following statements in incorrect?
A.
Cavitation affects the performance of a turbine to a lesser degree than that of a pump.
B.
Thoma’s cavitation parameter has different expressions for turbines and pumps.
C.
With the increase in pump speed, there is increase in its minimum net positive suction head requirement.
D.
The leading edge of blades in pumps and the trailing edge of blades in water turbines are more susceptible to cavitation damage
Answer»
B. Thoma’s cavitation parameter has different expressions for turbines and pumps.
192.
A centrifugal pump is taking much of power, the probable reason may be
A.
Liquid being pumped is heavy
B.
Speed of the pump is low
C.
There is leakage of air
D.
Ineffective strainer and foot valve arrangement.
Answer»
A. Liquid being pumped is heavy
193.
In rotodynamic pumps, the increase in energy level is due to
A.
Centrifugal energy only
B.
Pressure energy only
C.
Kinetic energy only
D.
Combination of a, b and c.
Answer»
D. Combination of a, b and c.
194.
In a pump there is
A.
Accelerating flow
B.
Decelerated flow
C.
Either of the above
D.
None of the above.
Answer»
A. Accelerating flow
195.
In a centrifugal pump the regulating valve is provided on
A.
The suction pipe
B.
Delivery pipe
C.
The casing
D.
None of the above.
Answer»
B. Delivery pipe
196.
In a centrifugal pump the sum of suction head and delivery head is known as
A.
Monomeric head
B.
Total head
C.
Static head
D.
None of the above.
Answer»
C. Static head
197.
Regarding manometric head (Hmano) which of the following relations is correct?
A.
Hmano= head imparted by the impeller to the liquid – loss of head in the pump
B.
Hmano= static head + losses in pipes + Vd2/2g
C.
Hmano= total head at outlet of the pump - total head at inlet of pump
D.
All of the above.
Answer»
D. All of the above.
198.
The ratio of power outlet of the pump to the power input to the pump is known as
A.
Mechanical efficiency
B.
Overall efficiency
C.
Monomeric efficiency
D.
None of the above.
Answer»
B. Overall efficiency
199.
The flow ratio in case of a centrifugal pump varies from
A.
0.1 to 0.25
B.
0.25 to 0.40
C.
0.40 to 0.50
D.
0.50 to 0.65
Answer»
A. 0.1 to 0.25
Chapter: Hydraulic Machines
200.
..... is a device which increases the intensity of pressure of a given liquid with the help of low pressure liquid of large quantity.
