CWT–04
Booklet No.:
Booklet Series:
03092014
Fluid Mechanics
Civil Engineering
A
Student Name:
Roll Number:
Duration: 90 Minutes
PAPER
MAXIMUM MARKS: 60
INSTRUCTIONS
1.
IMMEDIATELY AFTER THE COMMENCEMENT OF THE EXAMINATION, YOU SHOULD CHECK THAT THIS TEST BOOKLET
DOES NOT HAVE ANY UNPRINTED OR TORN OR MISSING PAGES OR ITEMS ETC. IF SO, GET IT REPLACED BY A
COMPLETE TEST BOOKLET.
2.
This Test Booklet contains 30 questions. Each question comprises four responses (answers). You will select the
response which you want to mark on the Answer Sheet. In case you feel that there is more than one correct
response, mark the response which you consider the best. In any case, choose ONLY ONE response for each item.
3.
You have to mark all your response ONLY on the separate Answer Sheet provided.
4.
All items carry equal marks.
5.
Before you proceed to mark in the Answer Sheet the response to various items in the Test Booklet, you have to fill
in some particulars in the Answer Sheet as per instructions.
6.
Each questions 2 marks and 2/3 negative mark is assigned for the wrong answer.
QH ENGINEERS ZONE EDUCATION PVT. LTD.
65/C, Prateek Mar ket, Near Canara Bank, Munirka, New Delhi -110067,
Ph(011) -26194869, Cell: 9873000903, 9873664427 , 8860182273:
E-mail: qhengineer zone@gmail.com ,website: www.qhengineerszone.com
1
QH Engineers Zone, 65/C, Near Prateek Market, Canara Bank, Munirka, New Delhi-110067,
P h ( 0 1 1 ) - 2 6 1 9 4 8 6 9 , C e l l : 9 8 7 3 0 0 0 9 0 3 , 9 8 7 3 6 6 4 4 2 7 : E - ma i l : q h e n g i n e e r z o n e @ g ma i l . c o m
Fluid Mechanics (CE)
(1.)
A flouting body attains stable equilibrium if its meta-centre is
(a.) At the centroid
(b.) Above the centroid
(c.) Below the centroid
(d.) Anywhere
Ans: b
(2.)
Gauge pressure is
(a.) Absolute pressure – atmospheric pressure
(b.) Absolute pressure + atmospheric pressure
(c.) Atmospheric pressure – absolute pressure
(d.) None of these
Ans: a
(3.)
Unit of kinematic viscosity is
(a.) m2/sec
(b.) Newton sec/m2
(c.) Newton sec/m3
(d.) kg sec /m2
Ans: a
(4.)
Euler’s equation for motion of liquids is given by
(a.)
(b.)
(c.)
dp

dp

dp

 gdz  vdv  0
 dgz  vdv  0
 gdz  vdv  0
(d.) dp  gdz  vdv  0
Ans: c
(5.)
Reynold number is the ratio of initial force and
(a.) Viscosity
(b.) Elasticity
(c.) Gravitational force
(d.) Surface tension
Ans: a
2
EN G IN EER S ZO N E, 6 5 / C , P r at ee k Ma r k et , Ne ar C an a ra B an k, Mu n i r ka, N ew Del h i -1 1 0 0 6 7 ,
P h (0 1 1 ) -2 6 1 9 4 8 6 9 , C e l l: 9 8 7 3 0 0 0 9 0 3 , 9 8 7 3 6 6 4 4 2 7: E - ma i l : q h en gi n e er zo n e @ g m ai l . co m
Fluid Mechanics (CE)
(6.)
Flow in aipex is laminar if Reynold number is
(a.) Less than 2100
(b.) More than 3000
(c.) Between 2100 and 3000
(d.) None of these
Ans: a
(7.)
Orifice-meter is used to measure
(a.) Pressure at the point
(b.) Discharge
(c.) Average speed
(d.) Velocity
Ans: b
(8.)
Evation of continuity of flow is based on the principle of conservation of
(a.) Mass
(b.) Momentum
(c.) Force
(d.) None of these
Ans: a
(9.)
If Cv , Cc , Cd and C r are the hydraulic coefficient of an orifice, then
(a.) Cd  Cc  Cv
(b.) Cr  1 
CV 2
Cd
(c.) Cv  Cc  Cd
(d.) Cc 
Cc
Cd
Ans: a
(10.)
The discharge through a V-notch weir varies as
(a.)
(b.)
H
1
H
(c.) H 3/2
(d.) H 7/2
3
EN G IN EER S ZO N E, 6 5 / C , P r at ee k Ma r k et , Ne ar C an a ra B an k, Mu n i r ka, N ew Del h i -1 1 0 0 6 7 ,
P h (0 1 1 ) -2 6 1 9 4 8 6 9 , C e l l: 9 8 7 3 0 0 0 9 0 3 , 9 8 7 3 6 6 4 4 2 7: E - ma i l : q h en gi n e er zo n e @ g m ai l . co m
Fluid Mechanics (CE)
Ans: d
(11.)
A piezometer opening in pipe measures
(a.) Velocity head
(b.) Static pressure
(c.) Total pressure
(d.) Negative static pressure
Ans: b
(12.)
The discharge through a siphon spillway is
(a.) Cd  a 2gH
(b.) Cd  a 2g  H 3/2
(c.) Cd  a 2g  H 2
(d.) Cd  a 2g  H 5/2
Ans: a
(13.)
According to Bernoulli’s equation
(a.) Z 
P v2

 constant
W
g
(b.) Z 
P v2

 constant
W 2g
(c.) Z 
P v2

 constant
W
g
(d.) Z 
P v2

 constant
W 2g
Ans: b
(14.)
A fluid having no viscosity is known as
(a.) Real fluid
(b.) Ideal fluid
(c.) Newtonian fluid
(d.) Non-Newtonian fluid
Ans: b
(15.)
The discharge over a right angled notch is
(a.)
4
8
Cd 2g .H
15
EN G IN EER S ZO N E, 6 5 / C , P r at ee k Ma r k et , Ne ar C an a ra B an k, Mu n i r ka, N ew Del h i -1 1 0 0 6 7 ,
P h (0 1 1 ) -2 6 1 9 4 8 6 9 , C e l l: 9 8 7 3 0 0 0 9 0 3 , 9 8 7 3 6 6 4 4 2 7: E - ma i l : q h en gi n e er zo n e @ g m ai l . co m
Fluid Mechanics (CE)
(b.)
8
Cd 2g  H 3/2
15
(c.)
8
Cd 2g  H 2
15
(d.)
8
Cd 2g  H 5/2
15
Ans: d
(16.)
A vertically immersed surface is shown below the distance of its centre of pressure from the water
surface is
(a.)
bd 2
x
12
(b.)
d2
x
12x
(c.)
b2
x
12
(d.)
d2
x
12
Ans: b
(17.)
The example of non-newtonian fluid is the flow of
(a.) Kerosene oil
(b.) Tooth paste
(c.) Diesel
(d.) Water at 100°C
Ans: b
(18.)
The Value of polytropic index n in polytropic state of atmosphere varies between
(a.) 1.2 to 1.4
(b.) 1.4 to 1.6
5
EN G IN EER S ZO N E, 6 5 / C , P r at ee k Ma r k et , Ne ar C an a ra B an k, Mu n i r ka, N ew Del h i -1 1 0 0 6 7 ,
P h (0 1 1 ) -2 6 1 9 4 8 6 9 , C e l l: 9 8 7 3 0 0 0 9 0 3 , 9 8 7 3 6 6 4 4 2 7: E - ma i l : q h en gi n e er zo n e @ g m ai l . co m
Fluid Mechanics (CE)
(c.) 1.6 to 1.8
(d.) 0.9 to 1.0
Ans: a
(19.)
The Chezy’s coefficient C is related to Darcy-Weisback’s friction coefficient f by
(a.) c  8
(b.) c  8
g
f
(c.) c  4
(d.) c  4
g
f
g
f
g
f
Ans: a
(20.)
A channel will have turbulent flow if the
(a.) Re  600
(b.) Re  1200
(c.) Re  1500
(d.) Re  2000
Ans: d
(21.)
An ideal flow of a liquid obeys
(a.) Continuity equation
(b.) Newton’s low of viscosity
(c.) Newton’s second law of motion
(d.) Dynamic viscosity land
Ans: a
(22.)
6
Critical depth (n) of a Channel, is
(a.) h 
v2
g
(b.) h 
v2
2g
(c.) h 
v
2g
(d.) h 
v
g
EN G IN EER S ZO N E, 6 5 / C , P r at ee k Ma r k et , Ne ar C an a ra B an k, Mu n i r ka, N ew Del h i -1 1 0 0 6 7 ,
P h (0 1 1 ) -2 6 1 9 4 8 6 9 , C e l l: 9 8 7 3 0 0 0 9 0 3 , 9 8 7 3 6 6 4 4 2 7: E - ma i l : q h en gi n e er zo n e @ g m ai l . co m
Fluid Mechanics (CE)
Ans: a
(23.)
The imaginary line drawn such that the tangents at its all points indicate the direction of the
velocity of the fluid particle at each point, is called
(a.) Path line
(b.) Stream line
(c.) Potential line
(d.) Streak line
Ans: b
(24.)
Inside pressure in a hollow soap bubble in air is
(a.)
4
d
(b.)
2
d
(c.)
6
d
(d.)
8
d
Ans: d
(25.)
If Re in the Renold’s number, the coefficient of friction for laminar flow is
(a.)
4
Re
(b.)
8
Re
(c.)
12
Re
(d.)
16
Re
Ans: d
(26.)
The velocity of flow at the critical depth ( hc ) is called critical velocity ( Vc ) which is equal to
(a.) Vc  g  hc
(b.) Vc  g  hc
(c.) Vc  3 g  hc
(d.) None of these
Ans: b
7
EN G IN EER S ZO N E, 6 5 / C , P r at ee k Ma r k et , Ne ar C an a ra B an k, Mu n i r ka, N ew Del h i -1 1 0 0 6 7 ,
P h (0 1 1 ) -2 6 1 9 4 8 6 9 , C e l l: 9 8 7 3 0 0 0 9 0 3 , 9 8 7 3 6 6 4 4 2 7: E - ma i l : q h en gi n e er zo n e @ g m ai l . co m
Fluid Mechanics (CE)
(27.)
For critical depth of flow of water in open channel, f c the specific energy must be
(a.) Minimum
(b.) Maximum
(c.) Average of maximum and minimum
(d.) None of these
Ans: a
(28.)
Specific energy of a flowing fluid per unit weight is
(a.)
p v

w 2g
(b.)
p
v

w 2g
(c.)
v2
h
2g
(d.)
p v2

h
w 2g
Ans: c
(29.)
For a most economical rectangular channel, the depth of the channel must be
(a.) Equal to depth of flow
(b.) Twice the depth of flow
(c.) Half the depth of flow
(d.) None of these
Ans: b
(30.)
Total energy line is
(a.) Pressure lead
(b.) Datum lead
(c.) Kinetic lead
(d.) All the above
Ans: d
(31.)
The best side slope for most economical trapezoidal section is
(a.) 30°
(b.) 45°
(c.) 60°
(d.) None of these
8
EN G IN EER S ZO N E, 6 5 / C , P r at ee k Ma r k et , Ne ar C an a ra B an k, Mu n i r ka, N ew Del h i -1 1 0 0 6 7 ,
P h (0 1 1 ) -2 6 1 9 4 8 6 9 , C e l l: 9 8 7 3 0 0 0 9 0 3 , 9 8 7 3 6 6 4 4 2 7: E - ma i l : q h en gi n e er zo n e @ g m ai l . co m
Fluid Mechanics (CE)
Ans:
(32.)
For an irrotational flow, the equation
 2  2

 0 is given by
 x 2  y2
(a.) Cauchy-Riemann
(b.) Reynold
(c.) Laplaces
(d.) Bernoulli
9
EN G IN EER S ZO N E, 6 5 / C , P r at ee k Ma r k et , Ne ar C an a ra B an k, Mu n i r ka, N ew Del h i -1 1 0 0 6 7 ,
P h (0 1 1 ) -2 6 1 9 4 8 6 9 , C e l l: 9 8 7 3 0 0 0 9 0 3 , 9 8 7 3 6 6 4 4 2 7: E - ma i l : q h en gi n e er zo n e @ g m ai l . co m
Fluid Mechanics (CE)
Answer Key
(1.)
(10.)
(19.)
(28.)
(2.)
(11.)
(20.)
(29.)
(3.)
(12.)
(21.)
(30.)
(4.)
(13.)
(22.)
(31.)
(5.)
(14.)
(23.)
(32.)
(6.)
(15.)
(24.)
(33.)
(7.)
(16.)
(25.)
(8.)
(17.)
(26.)
(9.)
(18.)
(27.)
10
EN G IN EER S ZO N E, 6 5 / C , P r at ee k Ma r k et , Ne ar C an a ra B an k, Mu n i r ka, N ew Del h i -1 1 0 0 6 7 ,
P h (0 1 1 ) -2 6 1 9 4 8 6 9 , C e l l: 9 8 7 3 0 0 0 9 0 3 , 9 8 7 3 6 6 4 4 2 7: E - ma i l : q h en gi n e er zo n e @ g m ai l . co m