Mechanical properties of fluids practice · Mixed difficulty

Coatings used on raincoat are waterproof because they

Work $W$ is required to form a bubbles of volume $V$ from a given solution. What amount of work is required to be done to form a bubble of volume $2V$ ?

Assertion: A solid sphere placed in the fluid under high pressure is compressed uniformly on all sides.
Reason: The volume of solid sphere will decrease with change of its geometrical shape.

A cubical block is floating in a liquid with half of its volume immersed in the liquid. When the whole system accelerates upwards with acceleration of $g / 3$, the fraction of volume immersed in the liquid will be

The surface tension of soap solution is $0.03\mathrm{N}{\mathrm{m}^{ - 1}}$. the work done in blowing to from a soap bubble of surface area $40\mathrm{c}{\mathrm{m}^2},\left( {\mathrm{in J}} \right),\mathrm{is}$

With the increase in temperature viscosity of a liquid -

Assertion:- Under steady flow the velocity of the particle of fluid is not constant at a point.
Reason:- Ideal fluids are compressible.

If a glass rod is dipped in pure mercury and removed, then mercury does not stick to the rod. This is because

A cork is submerged in water by a spring attached to the bottom of a bowl. When the bowl is kept in an elevator moving with acceleration downwards, the length of spring

Surface tension of a soap solution is able of 2.0 cm diameter will be

A man is sitting in a boat which is floating in a pond. If the man drink some water from the pond, what will happen to the level of water in the pond?

Given below are two statements:
Statement I: The contact angle between a solid and a liquid is a property of the material of the solid and liquid as well.
Statement II: The rise of a liquid in a capillary tube does not depend on the inner radius of the tube.
In the light of the above statements, choose the correct answer from the options given below:

Two narrow bores of diameter $3.0 \mathrm{~mm}$ and $6.0 \mathrm{~mm}$ are joined together to form a U-tube open at both ends. If the U-tube contains water, what is the difference in its levels in the two limbs of the tube? Surface tension of water at the temperature of the experiment is $7.3 \times 10^{-2} \mathrm{~N} / \mathrm{m}$. Take the angle of contact to be zero and density of water to be $1.0 \times 10^3 \mathrm{~kg} / \mathrm{m}^3$. (take, $g=9.8 \mathrm{~m} / \mathrm{s}^2$).

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

Terminal velocity of a small sized spherical body having radius $r$ falling vertically in a viscous medium having coefficient of viscosity $\eta$ depends on radius of body and coefficient of viscosity as

A hydraulic lift is designed such that cross sectional area of its arms are $5 \mathrm{~cm}^2 \, \& \, 10 \mathrm{~m}^2$. Find the force applied by mechanic on smaller area in order to lift a car of $5000 \mathrm{~kg}?$

A denotes the area to the right on the cube $h$ the depth of an orifice of area of cross-section$A$, below the liquid surface. The velocity of the liquid flowing through the orifice is

Aerofils are so designed that the speed of air

A liquid flows through a pipe of non-uniform cross-section. If ${A_1}$ and ${A_2}$ are the cross-sectional area of the pipe at two points, the ratio of velocities of the liquid at these points will be

A large number of droplets, each of radius $a$, coalesce to form a bigger drop of radius $b$. Assume that the energy released in the process is converted into the kinetic energy of the drop. The velocity of the drop is $(S=$ surface tension and $\rho=$ density of drop)

Unit in SI system and dimensions respectively of Reynold’s number are:

When a cube is placed in water at $4^{\circ} \mathrm{C}$, the fraction of volume of it submerged in water is ' $x$ '. When the temperature of water is $20^{\circ} \mathrm{C}$ the fraction of volume of it submerged in water becomes ' $y$ '. If the volume of the cube does not change with temperature then

A number of little droplets of a liquid of surface tension $T$, density $\rho$, all of same radius $r$, combine to form a single drop of radius $R$. If the total energy released in this process is converted into kinetic energy of the bigger drop, velocity of the bigger drop is

A metallic sphere of mass $M$ falls through glycerine with a terminal velocity $v_t,$ If we drop a ball of mass $27 {M}$ of same metal into a column of glycerine, the terminal velocity of the ball will be:

The terminal velocity of a ball in air is $v$, where acceleration due to gravity is $g$. Now the same ball is taken in a gravity free space where all other conditions are same. The ball is now pushed at a speed $v v$, then

Surface tension depends on

Statement A: The viscosity of liquid decreases with rise of temperature.
Statement B: Viscosity of a liquid is the property of the liquid by virtue of which it opposes the relative motion among its different layers.

The property utilized in the manufacture of lead shots is

The rain drops are in spherical shape due to

Assertion: At depth $h$ below the water surface pressure is $p$. Then at depth $2 h$ pressure will be $2 p$. (Ignore density variation).

Reason: With depth pressure increases linearly.