The ratio of the normal force of jet of water on a plate inclined at an angle of 30° as compared to that when the plate is normal to jet, is
1/√2
1/2
1
√2
Correct Answer :
B. 1/2
Related Questions
In impulse Turbine, energy available at the inlet is in the form of
Potential Energy
Strain Energy
Kinetic energy
None of these
A hydraulic ram is a device used to
Store the energy of water
Increase the pressure of water
To lift water from deep wells
To lift small quantity of water to a greater height when a large quantity of water is available at a smaller height
The speed of an imaginary turbine, identical with the given turbine, which will develop a unit power under a unit head, is known as
Normal speed
Unit speed
Specific speed
None of these
The speed ratio in case of Francis turbine varies from
0.15 to 0.3
0.4 to 0.5
0.6 to 0.9
1 to 1.5
According to fan laws, at constant speed and capacity, the pressure and power vary
Directly as the air or gas density
Inversely as square root of density
Inversely as density
As square of density
A hydraulic intensifier normally consists of
Two cylinders, two rams and a storage device
A cylinder and a ram
Two coaxial rams and two cylinders
A cylinder, a piston, storage tank and control valve
A turbine pump is basically a centrifugal pump equipped additionally with
Adjustable blades
Backward curved blades
Vaned diffusion casing
Inlet guide blades
The specific speed of a turbine is given by the equation
N√P / H3/2
N√P / H²
N√P / H5/4
N√P / H3
The Fourneyron turbine is _________ reaction turbine.
An axial flow
An inward flow
An outward flow
A mixed flow
The specific speed (Ns) of a centrifugal pump is given by
(N√Q)/H2/3
(N√Q)/H3/4
(N√Q)/H
(N√Q)/H5/4
The type of centrifugal pump preferred for a specific speed of 20 r.p.m. is
Slow speed pump with radial flow at outlet
Medium speed pump with radial flow at outlet
High speed pump with radial flow at outlet
High speed pump with axial flow at outlet
In a centrifugal pump, the liquid enters the pump
At the top
At the bottom
At the canter
From sides
A double overhung Pelton wheel has
Two jets
Two runners
Four jets
Four runners
The specific speed from 160 to 500 r.p.m. of a centrifugal pump indicates that the pump is
Slow speed with radial flow at outlet
Medium speed with radial flow at outlet
High speed with radial flow at outlet
High speed with axial flow at outlet
Puck up the wrong statement about centrifugal pump
Discharge a diameter
Head a speed²
Head a diameter
Power a speed⁴
According to fan laws, at constant pressure, the speed capacity and power vary
Directly as the air or gas density
Inversely as square root of density
Inversely as density
As square of density
Impulse turbine is generally fitted
At the level of tail race
Little above the tail race
Slightly below the tail race
About 2.5 m above the tail race to avoid cavitations.
In centrifugal pumps, maximum efficiency is obtained when the blades are
Straight
Bent forward
Bent backward
Radial
When a piping system is made up primarily of friction head and very little of vertical lift, then pump characteristics should be
Horizontal
Nearly horizontal
Steep
First rise and then fall
Which of the following is not an impulse turbine?
Girad turbine
Turgo turbine
Pelton wheel
Kaplan turbine
The relation between hydraulic efficiency (ηh), mechanical efficiency (ηm) and overall efficiency (ηo) is
ηh = ηo × ηm
ηm = ηm × ηh
ηo = ηh × ηm
None of these
The Thomson's turbine is __________ reaction turbine.
An axial flow
An inward flow
An outward flow
A mixed flow
By fitting an air vessel to the reciprocating pump, there is always a saving of work done and subsequently saving of power. This saving in case of a single acting reciprocating pump is
39.2 %
48.8 %
84.8 %
88.4 %
In axial flow fans and turbines, fluid enters and leaves as follows
Radially, axially
Axially, radially
Axially, axially
Radially, radially
The discharge through a reaction turbine ________ with the increase in unit speed.
Decreases
Increases
Remain same
None of these
For small discharge at high pressure, following pump is preferred
Centrifugal
Axial flow
Mixed flow
Reciprocating
Which of the following turbine is preferred for a specific speed of 60 to 300 r.p.m.?
Pelton wheel
Francis turbine
Kaplan turbine
None of these
The hydraulic efficiency of an impulse turbine is maximum when velocity of wheel is _______ of the jet velocity,
One-fourth
One-half
Three-fourth
Double
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Low velocity
High velocity
Low pressure
High pressure
Francis, Kaplan and propeller turbines fall under the category of
Impulse turbines
Reaction turbines
Axial flow turbines
Mixed flow turbines