VPL

(5)x(7.2) (5'
f density x)x(136)x2.65 cm
Then, the height of the
block above mercury
ne liquid level
Scm-X2.35 cm

density P6:A of massm and density

ball
pis immersedin a liqid of
e liquid
density 3p at a depth h and released To what
heighr will
the ball jump up above the
swrface of liqid ?(neglect the
resistance of water and air)
in water

28g and
Sol Volume of ball V= Acceleration of ball inside the
liquid
p
is 36g,

net upthrust- weight (ol) mg

m Im
m
=2g (upwards)
velocity of ball while reaching at surface

V=V2ah =J4gh
4gh
The ball willjump toa height H= 2g 2h
2g

EXERCISE - I

Pressure and Buoyancy

1. A liquid can easily change its shape but a solid

12N can not because

rsed 1)The density of a liquid is smaller than that

of a solid
ethe
2) The forces between the molecules is stronger
in solid than in liquids

3) The atoms combine to form bigger

molecules in a solid

separation between the

4) The average
molecules is larger in solids

F
2. Consider the equations P=Lim and
As0 AS
P-P, =pgz, in an elevator accelerating upward

1) Both the equations are valid

in 2)The first is valid but not the second
ck
3) The second is valid but not the first

4) Both are invalid

13
 MECHA NICAL PROPERTIES OF FLUIDS PHYSICS
at the
pressure
The thee vesses shown in figure have same Suppose the surface of
tube isP,and the
hase sren Bqoal in a barometer
voumes ofaliquid are poured
in the three vessels The of mercury in the cup is pressure
Tnercry
Force on the base will surface P,.
th
be
)P =
P, = atmospheric
2)

3)P, =
0,

P=
atmospheric
P,

pressure,
= atmospheric
P,
pressure
,
pressure

=0
DMaximum
in vesscls 4) P,=P, =0
A
2)Maximum an
barometer kept
in
in vessels B 9. A
clevator
the elevator reads If
3)Maximum when it is at rest.
in vessels C
4)Bqual speed, the reading
in all the vessels increasing will
be
1)Zero
2)76 cm
Bqual mass of three
identical cyindrical
liquids are kept in
three 3)>76 cm 4)<76 cm
vessels A,B and C.
densities The
arePa-P-Pc with Pa <PB A piece of wood is floating
in
force on the <Pc. The 10.
water
base will be
)Maximum in vessel A
bottle. The bottle is connected
to an kepr
air
in a
2) Maximum Neglect the compressibility of purnirp
in vessels water.

3) Maximum in B more air is pushed into the

bottle
fromthe When
vessel C the piece of wood will float
4) Equal in all the with
(HC) purtin

vessels
1) Larger part in the water
Figure shows a siphon. The liquid shown is 2) Lesser part in the water
The pressure
Water.
the points A and B is
difference Pa -P,between 3) Same part in the water

1)400 N/m² 4) It will sink

2) 3000 N/m2 11. A metal cube is placed in

T
10cm
When water is filled in the
an
empty
vessel
vessel
3) 1000 Nm? sothat
cube is just the
completely immersedin
4) Zero the force the
on the bottom of water
the vessel in
with the cube
A beaker containing a liquid is
contact

kept inside a
big closed jar. If the 1) Will increase
air inside the
jar is
continuouslypumped out, 2) Will decrease
the pressure in the
near the bottom of
liquid
3) Will remain the same
the liquid will
1) Increase
4) Will become
2) Decrease zero

3) Remnain constant 12. A closed cubical box is

4)First decrease completely filled wit
and then increase water and is
accelerated horizontally towards
The pressure in right with an acceleration
a liquid at a. The resultant
two points in the nomal
same horizontal force by the water on
plane are equal. the top of the
Consider an box.
elevator 1) Passes
accelerating upward and through the centre of the
a car top
ccelerating on a horizontal
road. The above 2) Passes through a
tatement is correct point to the right of
in the
centre
) The car only 2) The elevator only
Both of them 3) Passes througha point to the left of the
4)Neither of them cente
4) Becomes
zero

DOCTORS SERIES for Long Term Students

 VOL-IB
PHYSICS
tank
A sealed

moveswith a containing
in the n
shown
iqid of
)
between

)
hpg
pa
the
horizontal
figure.
points A
The

ifference
ensiy o
acceleralion
andBis in a,as
3) hpg - lpa pressure AMECHANIC L
4) hpg +lpa
A boat with bricks is 3) -PROPERTIES OF

:
14.
4)W,W,
the bricks are FLUIDS
thrOWn
floating
on
)water

4)
rises
in

remains
the pond

same
into w the

2)
ater;, water.
the When
level
9, W,> W W,W,=
Pressure
1) l
is
W,
is a W,tN
is 4)decreases of and
the scalar W,+N,=a
A boat 2)It arearatio of quanity
15. containing may are force to because
thrown into the iseor is
the area
leaves.
water, the fall to veciorS and
ratio
lake
level When
5)Itarea of
he
both
force
is
1) remains same of they the magnitude
are
3) rises falls
2) water
in normal to
ratio
of of
he
the
force
the 4)It the
4) Z0. depend on area componentof
Ifthe weight of the none A hetorce

)
j6. pieceof the
size of
body in a liquid body moves wood the
are and wih a oatsin area
equal, will
Sinks chosen
thenupthrust on vertical
water
kept
the the 1)sink in a
2) Floats body acceleration a, beaker
2)Sinkdeeper in the the
wood
3) Just completely
immerses in with
deeper in
ihe
lguid if
is a
Completely lies
out side the 5)comnea<g iauid if upward
is a
the liquid
A wooden block with a out downward,
liquid more
7.
coin from ihe
floats in water with

and h as the height of

I as
the
water
placed

length
on its
top
, 4)downward,
Temain in
water.
wih
thne
same
Dosiion
>g
iquidif a
is
time the coin falls column.immsered 21.The relative to
into After weight of a lhe
water. some
Then W,when balloon
filled
with
is
W,
when
air by the Both are cmpty and
air.

under
same
sensitive weighedin
identical spring
balance and
1) conditions.
W,< W,,asthe
is weight of air
offset bythe in the
balloon
2)W,<W, force of
buoyancy onit.
due to the
I)ldecreases and h on the force of
increases filled buoyancy acüng
balloon.
2)lincreases andh 3) W,>
decreases W,,as the air inside
isat a
3)both 1 and h increase pressure and hence has greater
greater
the density that
4) both 1 and h decrease air outside.

4)W,=W, +weight of the air inside

A spring balance it
reads W,when a ball is
22. An astronaut
tries to fill ink in an ink
suspended from it. A weighing
machine reads artificial satellite. The ink
pen in an

W, whena tank of liquid is kept

on it. When 1) Will be filled
into the pen
the ball is immersed in
the liquid, the spring 2)Will not be filled
balance reads W,and the weighing machine 3)filling will depend upon the quality of ink
Teads W
4) nothing can be said

2CTORS SERIES for Long Term Students

 MECHANICAL PHYSICs
PROPERTIES OF FLUIDS
2.Amaess comteat ask led ith a liquid
ket ona s
table in vcom
The fore exerted
by the liquid on
the base of the ask is
W, The
force exerted by the
Sask on the table is W

a) WW,
Ww, ) The balnce
A
than
will

will
read more
2
read more B
) The force
exerted by the the walls
2) The balance
A will read
than
kg.
5
liquid on
3) The balance less kg.
of the flask
is (W,-W,) B will read more than
5 ke than 2kg
1)a. and c are corect B will and
The balance A and
2) b andd are 4) read
2k&.and
correct
3)a,c and d are respectilvely. s
correct based on
4) All are coect 26. Hydraulic brakes are
1)Pascal's law
2)
24. The vessel
Torricelli's law
shown in the figure has 4)Boyle's
of areas of cross -
twO sections 3) Newton's law law
section A,and A,. A liquid the following instrument
of density p fills both the 27. Which of
is
sections,up to a height
h in measuring gauge pressure? used
for
each. Neglect atmospheric pressure. 1) Thermometer 2)Barometer

3) Manometer 4)
Hydrometer
28. Pressure at a point inside a
liquid
on does
depend not

1)the nature of the liquid

a) The pressure at the base of the vessel 2) shape of the container

is

2hPg. 3) the depth of point belowthe

surface of
the
b) The force exerted by the liquid on
liquid
the base
of the vessel is 4) acceleration due to gravity at
2hp gA, that
point

c) The weightof 29. Which of the following instrument

the liquid is
is <2hpgA,. used to
measure the blood pressure in humans?
d)The walls of the vessel at the level X exert a
downward force hpg(A, - A,) on 1)Sphygmomanometer
the liquid.

1)a, and c 2) Spectrophotometer

are correct

2) b, c and d are correct 3) Spectrometer 4) Barometer

30. An Open vessel containing water is
3) a, c and d are correct given a

constant acceleration a in the

4) all are correct horizontal

direction. Then the free surface of water

gets
. The spring balance A read 2 k.g. with ab block sloped with the horizontal at an angle given
m suspended from it. A balance B reads 5kg. by
when a beaker with liquid is put on the pan of
the balance. The two balances are now so 1) =tan
2) =tanE
arranged that the hanging mass is inside the
liquid
situation.
in the beaker as shown in flg. In this 3) = sin
4) 9=cosE

DOCTORS SERIES for Long Term Students

PHYSICs
A
jar isVOLe
A 2 ed
with
solid having wo
.
ball
densites p, non
mde
dropped in of a and mixing
e the
position jar.It material liaide I
of
Following isshown in comesto density
respecively N
troe the MECHANCAL
for p, figure,equilibrium equalteo
and DaWhich of in 15. byhe the
he
2) P> >
PROPERIES
weght of
immersed
N)Nsolid parn
he
iuid
FLUIDS
OF

3) same sphere of
P<P< Radis
material
and a
fhe diaplace
boty
of are
oa holle

32. A
Percentage
the of
both
heoating nspere
a of
body is (R) spheres
volume
spheres areheid.
The just will
same
notbeimmersed of
density of Noating on :Upthrust
same
hguid. the the both

)
36. depends
The body body is surface on
displaced.
it will is same as of
liqui. ():Ilis volume of
slightly that of
1) the Butdifficult for a liquid
come back pushed
remain slowlyto
its
down.
Then (R) :
amels
camel
walks
feet
man to
easily walk on
on
earlier sand.
3))
sinkin submerged man have sand.
liquid where it is position hence larger
area
4)come left pressure is thanfeer
out less. of
The tube vigoursly
shown
1) 2 ANSVWERS
Liguid is of 2)2
flows uniform 6)2 3)3
the throughitat
a crOSS- section.. 7)2 4) 4
direction
8)1 5)4
exerts on theshown by the constant speed 11)3 9)4
tube arrows .The in 12)3
13) 4 10)3
iquid 16)3 14)2
17)4 15)1
18)1
21)3 22)2 19)3
20)4
23)2
26)1 24)4
1) a net force 27)3 25)3
to 28)2
2)a net force the right 31)3
32)3
29)1
30)1
to the left 33)3
3) a 36)1 34) 1
clockwise torque 35)2
4)an
anticlockwisetorque

1)
Assertion (A)
Reason (R) & EXERCISE -I
Both (A)and (R) are Questions Pressure and
true and (R) buoyancy
explanationof (A) is the
correct
1. The two
thigh bones (femurs),
2) Both (A) each of
and (R)are true sectional area 1Ocm cros

and (R) is not the a human body support the

upper pac
correct
explanation of (A) of mass 40kg.The
pressure sustained by ave
3) (A) is true but (R) is false
the femurs is

4) Both (A) and 1) 3×10°N/m

(R)are false 2)2x10NIm
3) 6x10°N/m
34. (A):Apiece of ice floats 4) Sx10° N/m
in water. The level of
2.. The desnsity of the
water remains atmosphere at sea
unchanged when the ice 1.29 kg/m². Assume that it does not cha
melts completely. altitude. Then how high would
:
(R) According to Archimede's principle, the
extend?
the at

loss in weight of the body in the 3 km

liquid is 1) 2) 7km 3)8 km

DOCTORS SERIES for Long Term Students

 MECHANICAL PROPERTIES OF FLUIDS
20% of the cube 20.Venturimeter

ne cube is placed It tis used to measure volume flow

e is outside the
2gh
rate

em is Q= A,
4
4)
5
ilt to withstand 21. Speed of eMux
The speed (Torricelli equation) with which wa
sthe structure
an oil well in ter get comes out form a pin hole made in side

be wallof container fluied with ideal liquid.

the sea to
currents.

table

sufficient Ve
h
but of relative

ed by a string R
En a liquid find
22.Range
base of container
4) 2.5 N The distance on ground form
where water get srickes

R=2Vhh'
hole is made at mid
5) 1 Range is maximum when
point of side wall.
10) 2
15) 1 EXERCISE -I
and Bernoulle 's theorem
Equation of continuity
with
d particles at flow is more likely for liquids
1. Streamline
the flow is viscosity
e,
1)High density,High
line flow.
density, Low viscosity
2) High
pressble and
viscosity
3) Low density,High
ct of area & density
4) Low viscosity,Low
speed, the roof
2. When the wind blows at a high
off because :
of a house is blown
the roof increases
1)the pressure under
2) Pressure above the roof increases
3) Pressure above the roof decreases

The wind pushes off the roof

4)
of a tap and
3. Water coming out of the mouth
falling vertically in streamline flow
forms a
me remians area of cross-section
tapering column, i.e., the
of the liquid column decreases as it moves
down. Which of the following is the most
accurate explanation for this?

tudents 119
 MECHANICAL PROPERTIES OF FLUIDS
is based on PHYSICS
Scent sprayer
law
1)Charle's
2)Boyle's law
principle
3)Archimedes
thecorem
1) As the 4)) Bernoulli's
water down,its
moves speed increa-
ses and hence 8. In old age arteries carrying blood
its pressure decreases. It is

become narrow in
then compressed by the atmosphere
body resulting in heh
2)Failing water in the blood pressure. This
tries to reach a terminal velocity
law follows
and hence reduces the area of cross - scction 1) Pascal's fron
law
to balance upward and
downward forces. 2) Stoke's

3)The mass of water flowing 3) Bernoulli's principle

past any cross
4) Archimedes principle
section must remain constant. Also, water is

almost incompressible. Hence, the rate of 9. closed vessel is half

filled

A
with
volume flow must remain constant. As this is a hole near the top of the water.
vessel Thb
IS cqual to velocity x area, the area decrease pumped out from this hole and

as velocity level will

increases. The water rise up
in
a)
4)The surface tension causes the exposed b) The pressure at the surface
the
of vesse
surface area the
of the liquid to decrease decrease water

continuously. c) The force by the water on the

4.
The speeds of air-flow on the upper and lower vessel will decrease bottomof
the

Surfaces of a wing of an aeroplane are v, and d) The density the liquid will
of
V, respectively. It A is the cross-sectional area 1) b and c are correct decrease

of the wing and'p' is the density of air, then 2) b, c and d are correct
the upward lift is
3) a, c and d are correct
1) 1/2pA (V,-V,) 2) 1/2p A (V,+V,)
4) all are correct
3) 1/2pA (v,-v,) 4) 1/2pA (V+V,)
10. Water and mercury are filled in two
5. Dynamic lift due to spinning is cylindric
vessels up to same height. Both
1) Magnus effect 2) Doppler
vessels
effect
hole in the wall near the bottom. The
have a
3)Pascal effect 4) Torricelli's effect velocity
of water and mercury coming out of the
A fluid is in streamline flow across a horizontal are y,and V,respectively.
pipe of variable area of cross section. For this
2) v, =13.6u,
which of the following statements is correct ?
3) v, =V, /13.6 4) v, =V13.6 u,
1) The velocity is maximum at the narrowest

part of the pipe and pressure is maximum at

11. A large cylindrical tank has a hole area Az
of
the widest part
its bottom. Water is poured in the tank by
of the pipe a
tutc
of equal cross-sectional area A ejecting waa
2) Velocity and pressure both are maximum at
at the speed u.
the narrowest part of the pipe
1) The water level in the tank will keep oa

3) Velocity and pressure both are maximum

at
rising
the widest part of the pipe
2) No water can be stored in the tank

4) The velocity is minimum at the narrowest 3) The water level will rise to a height y 12

part of the pipe and the pressure is minimum and then stop
at the widest part of the pipe 4)The water level will oscillate.

DOCTORS SERIES for Long Term Students

 PHYSICS
A
Cylindrical
Iiters of
drum,
water. It
opening at the open
out in
time arains at
botton. 10our ton,
the t,»
t, and the
last
10 next liters 10
1)4=4=y liters of conains
hrough a 30
in liters

There are
opposite
tank

between

out
is

thetwo
of the
two
sides of
open at

holes The
tank
inwMer small

adentical
thetop.
4)
2),>>

containingholes
furher
ime
>=y
ly

small
comes
furher
ime
Then,

M.
)

)
MECHANICAL
)velocity

3)C,
a,
acccleraton

Wateris
are
darecOrrect
PROPERTIES
increases
and
decreases
OF
becomes FLUIDs
and
2)a, becomes
constan
two holes, is a onthe correet b
net h. tube 4) c are erO
horizontal the Asthe lhquid.
difference
in The A withMowing
its is correct
Vh foorce tank axis correct
1)
will liaquid height a)andBinthe streamline
The

J4.
2)

A
h

vessel
is
4) h²
proportional
to
comes
experience a

)
b)shape
The
tubeat

The of the tube.

pressure

a)uniiform
The
are
pressure
and
moton
atAthe same
pressurehoriZontal.Consider

are

never
are
B
through a
two

equafor
points

horiZonta\evel.

equal.
equal if
any

containing a
depth to cross-section.
haspressure the
at a

the side licquid. a may tube

rate of
flow of A 1)band nonuniformbeequal has
wall hole 2)c c even
is doubledliquid is
hole of is are if (he
V.If the and
3)a,c darecorrect
made crOss-secon. tubc
size vessel, The
4)Al anddare
1) Velocity correct
of (area)
efflux is ofthe
is halved are correct
doubledbut 18. correct
ayBoth Water
rate of flows
velocity of flow B.A through
doubled efflux volumeVof two
A and
and rate 2V,
water jdentical
tubesA
of flow the through B passes and
velocity of
eftlux
are following
a)Flow
in
given
a
throughthe
tube
flow is
doubled remains in may be time.
Which of
same but b)FlowN both the tubes
correct?

4) Velocity rate of in are

of
efflux is c)Flow both the tubes steady
is are
is
quadrupled halved
but raate
of
à)FMow issteady in A but turbulent
When a body flow B
15.
is
steady in
1)b and c Bbut turbulent in

weighed in turbulent in A
apparent loss in it's a 2)a,b are correct
a) the weight is liquid the and care
upthrustof equal to 3)a,c and
b) weight liquid on the d arecorrect
of the body 4)all are corect
liquid correct
c)the displaced by the 19. There
differencein body asmall hole
is
weights of the
and liquid body in air tank filled near the
with a bottomof an
open
a)weight of liquid.The
ejected does speed of the
water dìsplaced not depend on water
by the body a)area of the
I)a,b, c hole
are corTect 2)
a,b are b) density
3)a, b, d are correct of the
liquid
corect 4)b, d are corect c)height of the
liquid formthe
l6.When hole
an air bubble d) acceleration
moves up from due to gravity
botom of a lake the 1)a andb are correct

a)velocity 2)c anddare corect

decreases and becomes zero
b)acceleration 3) a,c and d are correct
increases and becomes
zero 4)all are correct

DOCTORS SERIES for Long Term

Students
 MECHANICAL PROPERTIES OF FLUIDS PHYSICS
a) If y is increased from zero to
20. A liquid Nows through a horizontal tube. The H
and then

,
increase decrease.
velocities of the liquid inthe two
sections for =
which have areas of cross- section A, and A b) x is maximum y H/2.

maximum value of x is
are and,respectively. The difference in the c) The H.
levels of the liquid in the two vertical tubes mnaximum value x

of
ts d) The will

density of the liquid.

dependo

)a, b and c are correct

2) c and d are
correct

c and d are correct

3) a,

4) All are correct

a)The volume of the liquid flowing through
the tube (A) & Reason
(R)
in unit time is A,,: (Assertion
Questions
1) (A) and (R)
Both
are true and (R)is
o) u;-ui- 2gh (A) the
explanation of
d) The energy per unit mass of the liquid is the coteg
(A) and (R) are trueand (R)
same in both sections of the tube. 2) Both
of (A) is
1)a, c and correct explanation not the
d are corect
2)c and 3) (A) is true but (R)is false
d are correct
3) a, b and d are correct 4) Both (A)and (R) are false

4) all are corTect (A): When air is blown between

23. two
balls which are suspended ping
POn
21. In the figure, an ideal liquid flows through the freely
move closer the,
tube, which is of uniform cross - section. The
(R) : When air is blown between
liquid has velocities V, and Vg, and pressures two
balls the pressure between pingpong
PA and P: at points A and b respectively the
decreases balls
a) v, =g
b)v > VA 24. (A) : A spinning ball in a region of
uniform
wind motion, will get an
c)PA =PB downlift.
uplift
(o
B
d) P, >PA
(R) : Due to spin of the ball in a
region
of
1) a and b are correct 2) c and d are correct uniform wind motion, the difference
in
3) a and d 4)All
are correct are correct velocity of air flow is present between t
lower and upper position of ball, leadine
A tank, which is open at the top, contains a
to varying pressure.
liquid up to a height H. A small hole is made in
the side of the tank at a distance y below the
-ANSWERS
liquid surface. The liquid emerging from the
hole lands at a distance x from the tank. 1)3 2) 3 3) 3 4)3 5)1

6)1 7) 4 8)3 9) 1 10)1

11) 3 12) 3 13) 2 14) 3 15) 1

16) 3 17) 2 18) 2 19) 1 20) 1

21) 3 22)1 23) 1 24)1

DOCTORS SERIES for Long Term Students

 VOL-IB
PMYSICS

EXERCISE
orcontinuity -I|
yation
and
enters
Aliquid tube of
a

velocity 3
Bernoulli's
MECHANICAL
The
witha ms variable theorem
and leaves
from the crOss velocit of
he wing
through
the PROPERTIEs
ai OF
is half
of the wider narrowNer section the of an over
one. end wider lower the FLUIDs
tleaves the tube The whose end WIng is surface aeroplane is upper
is
velocity radius the net 5m is
and the 30m/s. If
40m/s and
surface of
) 1.2
3) 1Oms-!
ms-1
2)12
ms
with
which
air
1)
= force

3kglm
acting
mnass
on the
the
of the areaof
wing
that on

the
4)20 wing is is300kg
3)725N
and
ms
In a horizontal pipe 8. 2275 upward g=1Orn/s)
N 2) (Density of

10 Pa between two line A upward 4)

725N
pressure downward
2275N
The points
Aistance of 1 kmn. horiz.ontal
falls Section pipe of
by allows downward
kg of oil
when change in
separated by water tonon uniform
per the oil a velocity I
msl when flow cross
to the other is ( flows
kinetic
from energy
point. If
the throughit
is 50 with a
Density
of SOme othervelocity ofpressure
1,
oil
= 800 one point should be point, the
low has KPa at a
to be2
2) Kglm) 1)51.5 pressure at
ms at
D20 80 3) that
40 3)48.5 KPa point
work 9 kPa 2)100 kPa
The done by
A water 4) 24.25
water
pressure in
through a pipe of
forcing 20 litre hose cm in 2 kPa

radius 1 2m³ of bucket. If it diameter is used

pressure difference bucket, then takes 1 to fill a
acroSs a cm, if the
I)

3)
3x
4x
106J

106J
2)2 pipe
10J
is
×10°Pais leaves the
the
1)150 hose is,
speed v at
mninute to
fill
which the the
water
4)0.2 x
10J 3) 100cm/s 2)70 cm/s
Volume cm/s
of
the liquid 10. An 4) 106
cm/s
through a pipe of flowing L-shaped glass
diameter d is per second flowing water tube is just
where the radius is d, V. At a such that immersed in
the point against its
opening is
velocity flowing water.
V of
flowis current is v, If the pointing
speed of
4V then water
2)
3)
4)
Water is
flowingthrough
a
variable cross - section. The
horizontal pipe of
is 0.2 rate of volume
lit/sec.
The pressure is 30,000
flow

the area of
where Pa, at a
point 1)The water
cross - in the tube
5x10 m.The pressure at section is rises to
height
the point 2g
area of
cross-section is 104m² is
where the 2)The water in the tube
rises to height
1) 6000 Pa
2) 36000 Pa 3)The water in the 21
3) 24000 Pa tube does not
4) 30000 Pa 4)None of these rise at all

Air streamshorizontally 11. Water

across an aeroplane from a tap
emerges vertically
wing of
3m²
area wards with initial dow
weighing 250 kg. The velocity 4 ms
speed is 60m/s and 45 m/s over air
sectional area of the
.The cros
the top surface tap is A.The flow
is ste
and under the bottom and pressure is constant
surface respectively. of water. The
throughout the stre
What is the on the wing distance h
lift
? (Density of air tap, where the cross
vertically below
1.293 g/l) - sectional area o
(2
1)3000 N stream becomes
2) 3500N 7A, (g=10 is msy
3) 4000 N 4)3054 N m
1)0.5 2) 1 m 3) 1.5 m 4)
2.
0CTORS SERIES for Long Term Students
 MECHANICAL PROPERTIES OF FLUIDS A tank of height
5m is
full PHYSICS
of
I8.
having hole of cross-sectionalarea water.
12. Water is
flowing continuously from atap water that
lem²
03 The water velociy The volume of

an internal diameter 8 x will There

The diameter
of
this hole per second is (g = 10 come
as leaves the tap ms oy

the
it

water stream at
is

a
0.4

distance 2 x 10 'm below ) 10 ms 2) 10

ms
mls)

the tap is close to: 3) 10 ms 4)10-

ms
water has
1) 7.5 x10m 2)9.6x10'm 19. A tank full
of
of
a
small
fourth
3) 3.6x 10 m 4) 5.0x10'm bottom. If one

the
the
tank ishole
and
flows through an t, seconds remaining
13. Water contained in a tank threc.
emptied in t, empiet
2 em, under a constant the tank is
seconds.
oritice of diameter
iourhs
pressure difference of
10cm of water column. (4,4,)is
Then

)
The
orifice
a
The rate of flow of water through the
44 cc/s 2) 4.4 cc/s

3) 440 cc/s 4) 4400cc/s 20. A large tank

filled
waterto a with

made the to be emptied through a

smal|height
14. An orifice of area 10 sg. mm is at
ratio of the time hole
bottom of a vessel containing water to a height bottom.The taken at
h/2 and that
for t
from h to Ihe
What the force on to fall taken
of 1Om above the orifice. is
0 is for leve
to fall from h/2 to the
the vessel leve

15. A
1)9.98N 2) 9.3N
large water tank has a hole
3) 1.96N

in
4)19.6N

its wall near

1)2 -1 2) 5 2
1

3)

of
the bottom. the water level above the hole is
A cylindrical
tank base area A
21. has a
4.9m. The horizontal distance from the hole at hole of area 'a'at its bottom. At the smal

time
which the water touches the ground, if the tap starts to supply water int o
the l=0,:
tank at
The maximum
bottom of water tank is 4.9m above the ground rate of a m'/sec.
level
the

of
1) 9.8 cm 2)98 m 3) 9.8 m 4) 980 m in the tank is wale

A water tank which is on ground has an a

3)2a8
D.
1 2) 4)
aTangement to maintain a constant water level 2g
2ga?
of depth 60 cm. Through a hole on its vertical
tank has a1 hole of area
A cylindrical
wall at a depth of 20cm from the free surface 22.
2cmatix
bottom. If water poured into the tankfrom
is
water comes out and reaches the ground at a i
tube above it at the rate of
certain distance. To have the same
horizontal 100cmPs,then the

made at a depth of
maximum height upto which water can ie
range anotherhole can be
the tank is (Acceleration due to
cm
1) 30 2) 10 cm gravity

3) 40 cm 4) 50 cm (g = 10ms-2)

1)2.5 cm 2) 1.25 cm
holes in the wall.
A large open tank has two 3) 5.5 cm 4) 2.5 cm
Dne is a square hole of side 'L' at a depth 'y'

rom the top and the other is a circular hole of ANSWERS

R at a depth from the top. When
dius '4y'
1)2 2)2 3)2 4) 2 5)2
completely with water, the
e tank is filled

of water flowing out per second

6)4 2
7)N 8)3 9)4 10) 1

cantities
3
the two holes are the same. Then 13)3
value 14)3
m 11)2 12) 3 15)

is : 19)4 20) 1
R
16) 3 17) 1 18) 1
L
L
2aL 3) 4) 21)1 22)2
2r 2) 2
Term Studet
DOCTORS SERIES for Long