Fluid Dynamics

The drag force decreases as the speed of an object moving through fluid _________

A pipe varies uniformly in diameter from 2m to 4m. An incompressible fluid enters the pipe with velocity 16 m/s. What is velocity of fluid when it leaves the pipe?

Torricelli's theorem be written as:

A tiny droplet of oil of density 'ρ' and radius 'r' falls through air under force of gravity. If viscosity of air is 'η', the terminal velocity acquired by the oil drop is given by:

The blood vessels collapse when:

Conservation of mass of fluid flow leads to:

Stokes’ Law for steady motion in a fluid of infinite extent is given by:

Potential energy per unit volume is given by:

In Bernoulli’s equation, the term is called:

When fluid is incompressible, the quantity is constant.

An incompressible fluid flows through a pipe that becomes narrower in one section. The fluid speed increases in that region to maintain:

A fluid is flowing through a tube, to undergo transition from laminar to turbulent flow it's velocity must be:

When an object attains terminal velocity, its acceleration is:

The curved shape of an airplane wing causes air to move faster over the top surface. This leads to:

In a pipe of varying cross-section as fluid enters the narrower region, it exhibits:

Rain drops falling from sky reach the ground with:

Water flows through a constriction in horizontal pipe as it enters constriction, water's:

A parachutist is falling constant (terminal) velocity. Which statement is not correct?

The speed v of a liquid in a tube depends on the change in pressure ΔP and the density ρ of the liquid. The speed is given by the equation. v=k (ΔP/ρ) Where k is a constant that has no units. What is the value of n?

A hail and a rain drop of same radius are released from same height, then rain drop will reach

Two meter high tank is full of water, a hole is made in the middle of the tank. The speed of efflux is

The viscous drag on a small spherical body (moving with slow speed v) is proportional to

Which of the following is not the characteristic of turbulent flow

Two different liquids are flowing in two tubes of equal radius. The ratio of coefficients of viscosity of liquids is 52:49 and the ratio of their densities is 13:1, then the ratio of their critical velocities will be

Water is flowing through a tube of nonuniform cross-section, ratio of the radius at entry and exit end of the pipe is 3: 2. Then the ratio of velocities at entry and exit of liquid is

There is a hole of area A at the bottom of cylindrical vessel..Water is filled up to a height h and water flows out in t second. If water is filled to a height of 4h,it will flow out in time equal to

If two liquids of same volume but different densities ρ1 and ρ2 are mixed, then density of mixture is given

If two liquids of same masses but densities ρ1 and ρ2 respectively are mixed, then density of mixture is given by

A soap bubble assumes a spherical surface. Which of the following statement is wrong

When 106 small drops coalesce to make a new larger drop then the drop

Two droplets merge with each other and forms a large droplet. In this process

Water from two holes 3.3 cm and 4.7 cm above the ground have same horizontal range. The height of tank?

A liquid at outlet with velocity V, in horizontal tube; reaction force exerted by liquid upon tube” ‘is propositional to

There is a hole in a tank. of. water at the bottom. If pressure is. 3atm at bottom speed of efflux

"n" equal rain drops each of radius 2mm fall with terminal velocity of 8cms-1 each, if coalesce then Vt=32cms-1, what about n=?

Rate of flow in tube is V when pressure is P. If the pressure is made four times and radius is halved then what about V

A water tank of height 10m is on level ground two holes A and B are at 3m and 7m above the ground respectively, the water ejecting from both A and B will.

Velocity of efflux through a hole does not, depend on

If there were no gravity, which of the following will not be there for a fluid?

In stream line flow of liquid, the total energy of liquid is constant at

Two rain drops reach the earth with different terminal velocities having ratio 9:4. Then the ratio of their volumes is

A ball floats on surface of water in a container exposed to the atmosphere. Will the ball remain immersed at its depth or will it sink or will it rise if the container is covered and the air is removed?

If we stretch a pipe to double of its length then flow rate

If a body falls with terminal velocity then

Mass flow rate is

Two boats moving parallel to each other they will:

“t" is the time required to evacuate a tank filled of liquid, time required to evacuate 50% of liquid will be

Speed of efflux is V in a tank if the tank is placed on 2m high then speed of efflux will be

An ideal fluid flowing in two different pipes with speed with ratio of speed 4:1, the ratio of their radii

A big rain drop having terminal velocity of 32m/sec is divided into eight equal rain drops terminal velocity of each small drop will be

Two rain drops of radii are in the ratio 1:2, then ratio of their terminal velocities is

Two spherical bodies of (iron) and steel having same masses their ratio of radii are 1:4, what will the ratio of their terminal velocities

The speed of a fluid in an aerofoil is √3V and V, its up thrust force is

A tall container filled to height “h", it is emptied in time “t", if the container is filled to h/3 height, the time required to completely empty the container is

The pressure where the speed is doubled is

The cross section of a pipe is 2m2 with fluid flowing at the rate of 2m/sec, the volume. flow rate is

If we increase the temperature of gases, their viscosity

The nature of viscosity is

Equation of continuity is based on the

Two droplets each of radius ‘r’ are combined to form a new drop of radius 2r, theterminal speed of the new droplet is

The terminal velocity of eight droplets having same mass and size is Vt, when they are mixed together to form a single drop, their combined terminal velocity is

A mass of 10kg moves down with uniform speed of 2m/s. Its air resistance will be

If a body moves down with constant, Speed, its acceleration is

The acceleration of a body when falling through viscous medium is

A body falling in vacuum with some speed then which of the following is true:

Chose the correct option for a light and heavy body falling under gravity through vacuum.

The flow of fluid at low pressure is said to be

When the speed of fluid is low, the flow is said to be

An incompressible fluid that flows through a cylindrical pipe of radius '2r' at point A having radius 'r' at point B further along the direction of flow if the velocity at point A is v then velocity at point B is?

Two hail stones of radi in the ratio of 1:3 fall from a great height through the atmosphere then there terminal velocity are in the ratio of

The difference in pressure between the lower and upper surface of air plane?

The terminal velocity of a sphere of lead of radius 'r' falling through a viscous liquid varies with radius 'r' that

Venturi relation is one of application of

According to equation of continuity when water falls its speed increases while its cross sectional area

Eight spherical rain drops of same mass and radius are falling down with a terminal velocity of 6cm/s if they collapse to form 1 big drop what will be its terminal speed? (neglect the buoyant force or buoyancy due to air)

A rain drop of radius 'r' fall in air with a terminal speed vt what is the terminal speed of radius 2r

The equation η+1/2ρv2+ρgh constant implies that

The unit of ρgh is same as that of?

Bernoulli's equation relates which of the following quantities?

Bernoulli's equation is an accordance with?

A water hose of internal diameter 20 mm at the outlet discharges 30 kg of water in 60s then what will be the water speed at the outlet. Flow is steady and density of water is equal to 1000 kg m-3?

Velocity of water in 6 inch diameter pipe is 5ft s-1. Find the velocity in a 3 inch diameter pipe which connect with it?(both pipes flow full)

If viscosity of fluid is more, the thickness of boundary layer is

Viscous forces are not present in

Water falls from a tap, down the streamline

Water is flowing in a pipe of diameter 4 cm with a velocity 3 m/s. The water then enters into a tube of diameter 2 cm. The velocity of water in the other pipe is

A small drop of water falls from rest through a large height 'h' in air, the final velocity is

We have three beakers A, B and C containing glycerin, water and kerosene respectively They are stirred vigorously and placed on a table. The liquid which comes to rest at the earliest is

A good lubricant should have:

As the temperature of water increases, its viscosity

Velocity of water in a river is

The weight of an aero plane flying is balanced by

At what speed the velocity head at a stream of water be equal to 40 cm?

According to Bernoulli's equationP/ρg+h+1/2v2/g = constantThe terms A, B and C are called respectively

An application of Bernoulli's equation for fluid flow is found in

Water is flowing through a tube of non- uniform cross-section ratio of the radius at entry and exit end of the pipe is 3:2. Then the ratio of velocities at entry and exit of liquid is:

In a turbulent flow, the velocity of the liquid molecules in contact with the walls of the tube is:

Two drops of the same radius are falling through air with a steady velocity of 5 cm per sec. If the two drops coalesce the terminal velocity would be

A square plate of 0.1 m side moves parallel to a second plate with a velocity of 0.1 m/s, both plates being immersed in water. If the viscous force is 0.002 N and the coefficient of viscosity is 0.01 poise distance between the plates in m is

A cylindrical tank has a hole of 1 cm² in its bottom. If the water is allowed to flow into the tank from a tube above it at the rate of 70 cm3/sec then the maximum height up to which water can rise in the tank is:

There is a hole of area A at the bottom of cylindrical vessel. Water is filled up to a height 'h' and water flows out in 't' second if water is filled to a height 4h, it will flow out in time equal to

There is a hole in the bottom of tank having water. If total pressure at bottom is 3 atm (1 atm 105N/m²) then the velocity of water flowing from hole is:

A cylinder of height 20 m is completely filled with water. The velocity of efflux of water (in m/s) through a small hole on the side wall of the cylinder near its bottom is:

Air is streaming past a horizontal air plane wing such that its speed in 120 m/s over the upper surface and 90 m/s at the lower surface. If the density of air is 1.3 kg per metre3 and the wing is 10 m long and has an average width of 2m, then the difference of the pressure on the two sides of the wing of :

A manometer connected to a closed tap reads 3.5 x 105 N/m² When the valve is opened, the reading of manometer falls to 3.0 x 105 N/m², then velocity of flow of water is

The velocity of kerosene oil in a horizontal pipe is 5 m/s. If g = 10m/s then the height head of oil will be:

Water is moving with a speed of 5.18 ms^-1 through a pipe with a cross- sectional area of 4.20 cm3 The water gradually descends 9.66 m as the pipe increase in area to 7.60 cm3 The speed of flow at the lower level is:

Water enters through end A with speed v1 and leaves through end B with speed v2 of a cylindrical tube AB. The tube is always completely filled with water. In case I tube is horizontal and in case II it is vertical with end A upwards and in case III it is vertical with end B upwards We have v1=v2 for:

Two water pipes of diameters 2 cm and 4 cm are connected with the main supply. The velocity of flow of water supply line in the pipe of 2 cm diameter is:

In which one of the following cases will the liquid flow in a pipe be most streamlined?

An ice berg of density 900 Kg/m3 is floating in water of density 1000 Kg/m3 The percentage of volume of ice-cube outside the water is:

Equal masses of water and a liquid of density 2 are mixed together, then the mixture has a density of:

One end of the cylindrical pipe has a radius of 1.5cm. If water streams (density=1.0x103kg/m3) steadily out of it at 7.0m/s, the volume rate is:

Bermoulli's equation can be derived from the conservation of:

A larger water tank open at the top has a small hole in the bottom when the water level is 30m above the bottom of the tank, the speed of the water leaking from the hole is:

A fluid is undergoing incompressible flow which represents that:

The acceleration of a falling body in a fluid depends upon:

Eight drops of water each radius 2mm are falling through the air at a terminal velocity of 8cm/s. If they coalesce to form a single drop, the terminal velocity of the combined drop will be:

A metal sphere of radius r is dropped into a tank of water. As it sinks at speed v, it experiences a drag force F given by F=krv, where k is a constant. What are the SI base units of k?

Water flows from a 6.0cm diameter pipe into an 8.0cm diameter pipe. The speed in the 6.0cm pipe is 5.0m/s. The speed in the 8cm pipe is:

A two-meter-high tank is full of water. A hole is made in the middle of the tank. The speed of efflux is:

When a heavy coin fallsa short distance towards the ground it does not reach terminal velocity. Why is this so?

The viscous drag on small spherical body (moving with slow speed v) is propotional to

The speed v of a liquid leaving a tube depends on the change in pressure ΔP and the density ρ of the liquid. The speed is given by the equation. where k is a constant that has no units. What is the value of n?

A thin horizontal plate of area 0.036 m² is beneath the surface of a liquid of density 930 kg m−3. The force on one side of the plate due to the pressure of the liquid is 290 N. What is the depth of the plate beneath the surface of the liquid?

Pressure of a gas is directly proportional to:

A small leak is developed in a large water storage tank. If the height of water above the leakage is 10 m, then find the speed of efflux through the leak:

The product of cross-sectional area of the pipe and the fluid speed at any point along the pipe:

Stokes' Law is given as:

For the horizontal pipe, the fluid inside it is flowing horizontally then Bernoulli’s equation can be written as

What is the speed of an incompressible non-viscous liquid flowing out from ‘B’ containedin a container as shown in the figure? Where AB = 5 m and g = 10 m/s2.

Which of the following is the best graphical representation between drag force ‘F’ on a spherical object of radius ‘r’ and its speed ‘v’ through a fluid of viscosity ‘η’?

When the drag force is equal to the weight of the droplet, the droplet will fall with:

An object having spherical shape of radius ‘r’ experiences a retarding force F from a fluid of coefficient of viscosity ‘η’ when moving through the fluid with speed ‘v’. What is the ratio of retarding force to speed?

Flow speed of the fluid through a non-uniform pipe increases from 1 m/sec to 3 m/sec. If change in P.E. is zero, then pressure difference between two points will be: (density of the fluid = 1000 kg/m3).

If the speed of efflux through a small hole in a large tank is 9.8 m/s. Find the height at the fluid above the hole:

Root mean square velocity of a gas having pressure ‘P’ and density ‘ρ’ is given by:

Two sample of gases ‘1’ and ‘2’ are taken at same temperature and pressure but the ratio of number of their volume is V₁:V₂ = 2:3. What is the ratio of the number of moles of the gas sample?

The dimension of coefficient of viscosity is:

Mass flow per second of the fluid is given by:

S.I. Unit of rate of flow of a fluid :

When fluid is incompressible, it means:

Equation of continuity is expressed as:

Ideal fluid is:

A machine worker placed a cylinder with a diameter of 18 cm between the plates of a hydraulic press. If he applies a 4.25 x 105N force to the cylinder, the stress on the end of the cylinder due to the applied force is A x 107Pa. What is the value of A?

Water is flowing in a streamline motion through a horizontal tube. The pressure at a point in the tube is P where the velocity of now is v. At another point, where the pressure is P/2, the velocity of flow is: (density of water=ρ)

The density of blood is:

A maintenance crew is working on a section of a three-lane highway with only one lane open to traffic. This result is much slower traffic flow. The cars on this highway behave like:

A body moving on a fluid will experience:

How much more thumb pressure must a nurse use to administer an injection with a hypodermic needle of inside diameter 0.30 mm compared to one with inside diameter 0.60 mm? Assume that the two needles have the same length and that the volume flow rate is the same in both cases.

If each particle of fluid is passing through the same point, what would be the flow?

An object moving through a fluid experiences a retarding force known as drag force. The drag force _ as the speed of the object _