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What is the use of a filter pump ? How does it work ?

Important Questions on Mechanical Properties of Fluids

HARD
Air (density ρ ) is being blown on a soap film (surface tension T ) by a pipe of radius R with its opening right next to the film. The film is deformed and a bubble detaches from the film when the shape of the deformed surface is a hemisphere. Given that the dynamic pressure on the film due to the air blown at speed v is 12ρv2, the speed at which the bubble formed is
MEDIUM

What will be the nature of flow of water from a circular tap, when its flow rate increased from 0.18 L min-1 to 0.48 L min-1? The radius of the tap and viscosity of water are 0.5 cm and 10-3 Pa s, respectively. (Density of water : 103 kg m-3)

HARD
Consider the wall of a dam to be straight with height H and length L. It holds a lake of water of height hh<H on one side. Let the density of water be ρw Denote the torque about the axis along the bottom length of the wall by τ1. Denote also a similar torque due to the water up to height h2 and wall length L2 by τ2. Then, τ1τ2 (ignore atmospheric pressure) is
HARD

Consider the configuration of a stationary water tank of cross-section area A0 and a small bucket as shown in figure below;

Question Image

What should be the speed v of the bucket, so that the water leaking out of a hole of cross-section area A (as shown) from the water tank does not fall outside the bucket?

(Take, h=5 m, H=5 m, g=10 m s-2, A=5 cm2 and A0=500 cm2).

HARD
A bubble of radius R in water of density ρ is expanding uniformly at speed v. Given that water is incompressible, the kinetic energy of water being pushed is
MEDIUM
A hollow spherical shell at outer radius R floats just submerged under the water surface. The inner radius of the shell is r . If the specific gravity of the shell material is 278 with respect to water, the value of r is:
EASY
A air bubble of radius 1 cm in water has an upward acceleration of 9.8 cm s2. The density of water is 1 gm cm3 and water offers negligible drag force on the bubble. The mass of the bubble is g = 980 cm/s2.
EASY
Physical processes are sometimes described visually by lines. Only the following can cross
HARD
An iron block is suspended from a string and is then completely immersed in a container of water. The mass of iron is 1 kg and its density is 7200 kgm3. What is the tension in the string before and after the iron block is immersed ?
EASY

What is velocity profile? Draw the velocity profiles for a liquid flowing over a horizontal solid surface.

EASY
The diameter of a pipe at two points where a venturimeter is connected is 5 cm and 8 cm  and the difference of level in it is 4 cm. Calculate the mass of water flowing through the pipe per second.
EASY
A hydraulic automobile lift is designed to lift cars with a maximum mass of 3000 kg. The area of cross-section of the piston carrying the load is 425 cm2. What maximum pressure would the small piston have to bear?
EASY
Water is moving with a speed of 5.18 m s-1 through a pipe with a cross-sectional area of 4.20 cm2. The water gradually descends 9.66 m as the pipe increases in area to 7.60 cm2. The speed of flow at the lower level is
HARD
A piece of wood of volume 0.6 m3 floats in water. Find the volume exposed. What force is required to immerse it completely under water ? Density of wood =800 kgm3.
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MEDIUM
Two capillaries of length L and 2L and of radii R and 2R respectively are connected in series. The net rate of flow of fluid through them will be (Given, rate of the flow through single capillary, X=πpR4/8ɳL )
MEDIUM
A wide tank is filled with water and kerosene. The tank has a small hole at the bottom. The height of water layer is 40 cm and that of the kerosene layer is 30 cm. Find the velocity of the water flow, neglecting the viscosity. Given relative density of kerosene is 0.80.
MEDIUM
A jet of water having velocity=10 m s-1 and stream cross-section=2 cm2 hits a flat plate perpendicularly, with the water splashing out parallel to plate. Find the force that the plate experiences
EASY

Consider the following statements:

1. Taking into account, the fact that any object which floats must have an average density less than that of water during World War 1, a number of cargo vessels were made of concrete.

2. Concrete cargo vessels were filled with air.

3. A ship floats higher in the water on a high-pressure day than on a low-pressure day.

4. Floating of the ship in the water is not possible because of the buoyancy force which is present due to pressure difference.

Which of the statements given above are correct?

MEDIUM
What is critical velocity for a fluid motion? Which factors it depends upon?
HARD
What is Reynold's number? Explain its significance.