Fluids Questions and Answers

Equal volume of wo immiscible liquids of densities p and 2p are filled in a vesse 3h figure Two small holes are punched at depth and from the surface of ligh 2 and v are the velocities of efflux at these two holes then Date C 05 01 2019 5939 A7552 Answer 3h 2 1 A 2p Ngh Ah Applying Bernoulli s theorem b w B and C 1 P pv 2p gah P 2p V 0 Lokasi P pgh 0 2pg 2pg 2 P 2 2p V 2pgh pV V1 is V

er e 7 32 The tank in figure 7 108 discharges water at constant rate for all water levels above the air inlet R Find the height above datum to which water would rise in the manometer tubes M and N M Ans 20 cm 60 cm 40 cm open to atmosphere Figure 7 108 Datum

This section contains NUMERICAL VALUE TYPE questions Enter the correct A vessel containing liquid of density p is falling freely under gravity Pressure difference between two points A and B at a vertical height of H shown in figure will be At Read More B

AS 1000kg m is flowing steadily in a pipe of non uniform cross sectional area The area at wider section is 0 2m and the area at the narrower section is 0 1m The pipe lies in the horizontal plane The speed of liquid at point P is 2m s Determine the difference in pressures at P and Q P A 4000P a OT 5000D 11

7 71 Water and oil are poured into the two limbs of a U tube containing mercury figure 7 128 The interfaces of the mercury and the liquids are at the same height in both limbs Determine the height of the water column h if that of the oi h 20 cm The density of the oil is 0 9 TA Figure 7 128 h

For the inclined tube manometer shown below the pressure in pipe A is 0 05 bar g The fluid in both pipes A and B is water and the gauge fluid in the manometer has a specific gravity of 2 6 What is the absolute pressure in B corresponding to the differential reading shown Select one O a 1 063 bar g O b 1 038 bar g c 1 038 bar abs O d 1 063 bar abs 7 5 cm 20 cm 30 SG 2 6 7 5 cm

7 74 A cylindrical tank with a height h 1 m is filled with water up to its brim a what time is required to empty the tank through an orifice at its bottom it the cross sectional area of the orifice is 1 that of tank b Compare this time with that required for 400 om od 101 the same volume of water to flow out of the tank if the water 1990 Brusni level in the tank is maintained constant at a height h 1 m from the orifice Ans a 3 min b 1 5 min he

7 66 A sphere of radius R made from material of specific gravity SG is submerged in a tank of water The sphere is placed over a hole of radius a in the tank bottom For the dimensions given determine the minimum SG required for the sphere to remain in the position shown H 0 8 m R 20 mm

e melts uniformly cubical shape nd the length of es contact with 7 61 Water flows in a horizontal pipe whose one end is closed with a value and the pressure gauge falls to 1 x 105 N m when the valve is opened Calculate the speed of water flowing in the pipe Ans 20 m s

7 37 A large block of ice 5 m thick has a vertical hole drilled through and is floating in the middle of a lake What is the minimum length of a rope required to scoop up a bucket full of water through the hole Ans 105 ml

Two identical rings each of radius R are placed coaxially such that the distance between their centre i H Now a soap solution film is formed between the two rings such that there is no films in the circular regions bounded by the rings Let T be the surface tension of the solution then the total surface energ of the film will be Option A B C 4TRHT more than 4TRHT Less than 4 RHT Rate this que

7 34 A rubber ball with a mass M and radius R is submerged into a liquid of density p to a depth h and released What height will the ball jump up above the surface of water Neglect resistance of water and air 4 3 R p M h M Ans

57 39 An iron casting containing a number of cavities weights 6000 N in air and 4000 N in water What is the volume of the cavities in the casting Density of iron is 7 87 g cm Ans 0 12 m S

Figure shows cross sectional view of solid semi cylinder of radius r rigidly attached with solid triangular prism It floats on a liquid having density p It is in contact with smooth vertical wall Part BC is not in contact with liquid The length of object is Given AC CD DA The atmospheric pressure is Po independent of A Buoyant force acting on object is atmospheric pressure B Normal force exerted by vertical wall is pgr2 4 2 C The pressure force exerted by liquid on slant surface ADC of prism is 2 3 plg D Weight of object is 3 1 1 r pg B

23 Equal volumes of two immiscible liquids of de p and 2p are filled in vessel as shown in figure Two 3h from 2 the surface of lighter fluid If V V are the velocities of efflux at these two holes Then v v is 3 h small holes are punched at depth 2 and 1 1 2 2 4 2p 2 V 1 4 and

In a 2 d flow V jand p kat where t pare time s density kg m and is a constant and is equal to 1 kg s m What is the rate of change of density of a fluid particle at 1 1 at t 1 Select one a 0 25 kg m b 1kg m c 0 kg m d 0 5 kg m

A soap bubble has a radius 8mm The excess pressure inside the soap bubble is balanced by a liquid column of height 0 04cm The surface tension of the soap solution is 0 02N m Find out the density of the liquid Take g 10m s A 2000kg m B 2500kg m 3000kg m R 4000kg m

A tube of length 80 cm is submerged vertically inside a liquid with lower end 20 cm below the surface The upper end is now sealed and taken out gently It is found that 8 cm of the liquid still remains in the tube The atmospheric pressure is given by h cm of this liquid where h is 1 48 2 32 3 60 4 52

A large tank filled with a liquid whose density is 1100 kg m 3 is connected to a hose whose diameter is 6 cm at point B and 15 cm at point C The two point B and C are found to be at the same horizontal level and are held at a height H 2 m below the surface of the liquid in the tank Given vA 0 m s PA PC Patm g 10 m s2 then the volume flow rate is H 0 11775 kg s O 0 01788 kg s O 003176 kg s 0 0496 kg s A N B 00 Z U

When a block of iron floats in mercury at 0 C fraction k of its volume is submerged while at the temperature 60 C a fraction k is seen to be submerged If the coefficient of volume expansion of iron is Feand that of mercury is YHgthen the ratio k k can be expressed as O O O 1 607Fe 1 60YHg 1 60 Fe 1 60Hg 1 60 Fe 1 60YHg 1 60YHg 1 60 Fe

Water flows in a horizontal tube see figure The pressure of water changes by 700 Nm 2 between A and B where the area of cross section are 40 cm and 20 cm respectively Find the rate of flow of water through the tube density of water 1000 kgm 700 m AB 40 cm 3 20 cm 1000 kgm B

rminal velocity i e it is now falling at a constant velocity Use Fd to denote e drag force due to air resistance Please use the interactive area below to draw the Free Body Diagram for the ball Add Force Reset All I F d

c 3 25 10 N d 4 25 10 N 7 A steam of water flowing horizontally with a speed of 25 msgushes out of a tube of cross sectional area 10 m and hits at a vertical wall nearby What is the force exerted on the wall by the impact of water a 125 N b 625 N c 650 N d 1125 N

An ice block floats in a liquid whose density is less than water A part of block is outside the liquid When whole of ice has melted the liquid level will a rise b go down c remain same

A cylindrical block floats vertically in a liquid of density P kept in a container such that the fraction of volume of the cylinder inside the liquid is Then some amount of another immiscible liquid of density p p P is added to the liquid in the container so that the cylinder now floats just fully immersed in the liquids with x fraction of volume of the cylinder inside the liquid of density p The ratio PP will be WB JEE 2013 mg c 1 x X1 X X X 1 X1 X X d x2 1 b

A spherical liquid is object of mass 1 kg and radius Im is falling vertically downward inside a viscous liquid in a gravity free space At a certain instant the velocity of the sphere is 2m s If the coefficient of viscosity of the N s m2 then velocity of ball will become 0 5 m s after a time 1 18T 1 2 3 In4 s 2ln4 s 31n4 s

7 77 A vertical tube has diameter 0 016 m at its bottom end from which water flows out at the rate of 1 2 kg per minute The pressure at the end is atmospheric pressure 0 7 m of mercury If the diameter of the tube is 0 004 m at a height of 0 3 m from the bottom end find the pressure there

7 87 Water flows through a tube shown in figure 7 134 The areas of cross section at A and B are 1 cm and 0 5 cm respectively The height difference between A and B is 5 cm If the speed of water at A is 10 cm s find a the speed at B and b the difference in pressures at A and B B

Which of the following statements about a fluid at rest in a cup is are correct 1 Pressure is same at all the points in the fluid 2 Pressure is exerted on the walls 3 Pressure exists everywhere in the fluid 1 1 and 2 only 2 2 and 3 only 3 1 only

A viscous liquid is filled in a tank at room temperature In summer the temperature rises then what will effect on viscosity of the liquid 1 2 3 Increases Decreases Does not depend upon temperature First increase then decrease

7 58 A cube of ice of edge 4 cm is placed in an empty cylindrical glass of inner diameter 6 cm Assume that the ice melts uniformly form each side so that it always retains its cubical shape Remembering that ice is lighter than water find the length of the edge of the ice cube at the instant it just leaves contact with the bottom of the glass 50 0C

7 67 Two identical containers are open at the top and are connected at the bottom via a tube of negligible volume and a valve which is closed Both containers are filled initially to the same height of 1 00 m one with water the other with mercury as the drawing indicates The valve is then opened Water and mercury are immiscible Determine the fluid level in the left container when equilibrium is re established Water Valve Mercury

7 70 A water pipe with internal diameter of 2 cm carries water at the floor of a house with velocity 2 m s and at pressure 2 105 N m Another pipe of internal diameter 1 cm is connected to it and takes water to 1st floor 5 m above ground What is the velocity and water pressure at 1st floor Take g 10 m s Ans 8 m s 1 2 105 N m

18 A ring is cut from a platinum tube of 8 5 cm internal and 8 7 cm external diameter Its plane is kept horizontal so that it comes in contact with the water in a vessel What is the surface tension of water if an extra 3 97 g force is required to pull it away from water g 980 cm s 72 dyne cm 60 dynelem 2 14 dyne cm 4 36 dyne cm

and is 1000 kg m O 5 8x10 m 4 7 10 m 4 7 10 m 5 9x10 2 m 5 9x10 m O 4 6x10 1 m Question 16 1 A non viscous fluid flows to the right through a horizontal pipe that gets narrower by a factor two as shown P P V1 V2 V V Fluid flow direction Assume the flow is laminar and that points 1 and 2 are at the same height Which of the following relationships between the speeds v and pressures P at points 1 and 2 are correct V1 V2 10 22 2 3 pts

0 There is a hole of radius r at the bottom of a long cylindrical vessel of glass The depth to which the vessel can be lowered vertically in a deep water bath surface tension T and density p without any water entering inside is 0 0 37 b prg 27 prq d prg T pro

34 A large tank is filled with water density 103 kg m A small hole is made at a depth 10 m below water R on ground Approximately what extra pressure surface The range of water issuing out of the hole is must be applied on the water surface so that the range becomes 2R take 1 atm 105 Pa and g 10 m s a 9 atm c 5 atm 10m KR b 4 atm d 3 atm

A soap bubble of radius R starts collecting charge slowly and evenly on its surface till its radius becomes 2R If surface tension of soap water is s then the difference in pressure inside and outside the bubble is Select an answer A S R Q 327 ER

is opened Assume isothermal conditions Atmospheric pressure is p 105 Pa Pwater 10 kg m Water of density p is filled in a hemispherical bowl of radius R to its brim Find the total thrust force that water exerts on the wall of one of the quarter spheres The atmospheric pressure is Po Neglect surface tension first Calculate this force next taking the surface tension of water as S

Two capillary of length L and 2L and of radius R and 2R are connected in series The net rate of flow of fluid through them will be given rate to the flow through single capillary X PR4 8nL A 8 X 9 86 B 9 X C 5 5 7

A U tube of uniform cross section is partially filled with a liquid I Another liquid ll which does not mix with liquid I is poured into one side It is found that the liquid levels of the two sides of the tube are the same while the level of liquid l has risen by 2cm If the specific gravity of liquid l is 1 1 the specific gravity of liquid II must be A 1 12 C 1 05 B 1 1 D 1 0 II

Please explain this question with hel p of diagram i didn t understand the concept of thickness of dam relation with increasing pressure with depth How thickness affects working of da m 4 Liquid in B increases 36 Why the dam of water reservoir is thick at the bottom 1 Quantity of water increases with depth 2 Density of water increases with depth Pressure of water increases with depth de 4 Temperature of water increases with depth P

A hypothetical planet has an ocean of water which is 50 km deep The top 5 km is frozen as ice i e 45 km is water Radius and average density of the planet are both half the respective values for the earth There is no atmosphere Obtain an estimate of the pressure at the bottom of the ocean

A cuboidal piece of wood has dimensions a b and c Its relative density is d It is floating in a large body of water such that side a is vertical It is pushed down a bit and released The time period of SHM executed by it is 1 2T 3 2 abc g bc Vdg 2 2 4 2T g da da

34 A liquid is kept in a cylindrical vessel which is being rotated about a vertical axis through the centre of the circular base If the radius of the vessel is r and angular velocity of rotation is w then the difference in heights of the liquid at the centre of the vessel and the edge is 1 ro 2g 3 2grw 2 4 r w 2g

A student starts an experiment with a stack of three identical sheets of paper He crumples the stack against his fist as shown in the figure then separates a single sheet from the other two without altering their crumpled pseudo conical shape This yields two objects of the same shape but of different masses He releases these objects simultaneously and records their motion in still air After the two objects acquire their terminal velocities the heavier one moves n 2 times farther than the lighter one in a particular time interval If the force of air resistance is proportional to u where u is velocity and x is a constant exponent what should be value of the exponent x Two sheets One sheet

47 A U tube of cross section A and 2A contains liquid of density p Initially the liquid in the two arms are held with a level difference h as shown in figure After being released the levels equalize after some time The work done by gravity forces on the liquid in the process is a pAgh c pAgh2 6 A 2A b pAgh 3 d pAgh 3 4

Figure shows a soap film formed between two square figures made of a uniform wire The bigger square is held while keeping it in a horizontal plane and the smaller square is slowly allowed to drop vertically It reaches an equilibrium state after dropping a height h Let surface tension of soap T Mass per unit length of wire A Acceleration due to gravity g Given that h find the integer value n naga 2 4T g 4a

A straight glass tube is having sealed lower end and upper end is open to atmosphere The lower half of the tube is filled with n moles of a diatomic gas and the upper half is filled with mercury Atmospheric pressure is 76 cm of mercury and complete length of the tube is 152 cm Now the gas inside the tube is slowly heated How much heat in Joule must be provided to the gas such that all the mercury is been pushed out of the tube Given that Atmospheric pressure in S I unit x Area of cross section of the tube in S l unit x 0 76 m 16J Neglect any vibrational degree of freedom

56 A hollow object of volume V is immersed in a tank The object is tied to the bottom of the tank by two wires which make an angle 30 with the horizontal as shown in figure The object would float if it was set free and one fourth volume is immersed in liquid of density Po The tension in the wires is 12 Vpog 4 a b 30 30 3Vpog 4 c 5Vpog 4 d Vpog