Mechanical properties of fluids practice · Medium

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.

If the angle of contact is less than $90^{\circ}$, the pressure just inside the surface of a meniscus

If two soap bubbles of equal radii $r$ coalesce, then the radius of curvature of interface between two bubbles will be

A weightless bag is filled with 5 kg of water and then weighed in water. The reading of spring balance is

Statement I: A ship floats higher in water on a high
pressure day than on a low pressure day.
Statement II: Floating of ship in the water is possible
because of the buoyant force which is present due to the
pressure difference.

If a capillary tube is dipped and the liquid levels inside and outside the tube are same, then the angle of contact is

Bernoulli’s equation is valid for

A big drop of radius $\mathrm{R}$ is formed by 1000 small droplets of water, the radius $r$ of small drop is:

Which of the following is NOT an example of application of Bernoulli's principle?

Express standard atmospheric pressure in $\mathrm{Nm}^{-2}.$

Hydraulic lifts and hydraulic brakes are based
on

A: It is difficult for a man to walk on sand But camel walk easily on sand
R: Camels feet have larger area than feet of man hence pressure is less

Assertion: Pressure is a vector quantity.

Reason: Pressure $P=\frac{F}{A}$. Here $F$, the force is a vector quantity.

In a car lift compressed air exerts a force ${F_1}$ on a small piston having a radius of 5 cm. This pressure is transmitted to a second piston of radius 15 cm. If the mass of the car to be lifted is 1350 kg. Then ${F_1}$ is

The surface tension of a liquid decreases with a rise in

A square plate $0.15 \mathrm{~m}$ side moves parallel to second plate with a velocity of $0.1 \mathrm{~ms}^{-1}$ both plates being immersed in water. If the viscous force is $0.0025 \mathrm{~N}$ and the coefficient of viscosity 0.001 poise, distance between the plates is:

Find the height of the liquid in the capillary tube if surface tension of liquid is $S$, radius of capillary tube is $r$ and acceleration due to gravity is ${g}:$

The rate of flow of liquid in a tube of radius $r$, length $l$, whose ends are maintained at a pressure difference $p$ is $V=\frac{\pi N p r^4}{\eta l}$, where $\eta$ is coefficient of the viscosity and $N$ is

If a liquid neither rises nor depresses in a capillary, then it means that