Surface Tension

Q. Equal weight of methane and hydrogen are mixed in a container at 25 degree celcius . Fraction of total pressure exerted by methane is ??

Q.

Hairs of shaving brush cling together when it is removed from water due to

1. Force of attraction between hair

2. Surface tension

3. Viscosity of water

4. Characteristic property of hairs

Q. A square wire frame of side L is floating on the surface if liquid of surface tension T. The force required to pull out the frame from the liquid is ( in terms of T and l )

Q. Why rainwater falling is spherical in shape

Q. What is vdg in water up thrust

Q.

give reasons for the following-
a. Milk is called a liquid.

b. Carbon dioxide is a gas.

Q. A rectangular bar of soap has density 800 kg/m3 floats in water of density 1000 kg/m3. Bath oil of density 300 kg/m3 is slowly added, forming a layer that does not mix with the water. When the top surface of the oil is at the same level as the top surface of the soap, what is the ratio of the oil layer thickness to the soaps thickness, x/L?

Q. Three tins filled with water have holes of the same size and are kept on a level surface as shown.
The stream of water falls out the fastest through the:

1. middle hole in case (P).
2. upper hole in case (Q).
3. lowest hole in case (R).
4. upper hole in case (R).
   

Q. QAn air bubble is seen inside a solid sphere of glass(n=1.5) of 4cm diameter at a dis†an ce of 1cm from the surface of the sphere (on seeing along the diameter). Determine the real position of the bubble inside the sphere

Q. Why is air positively charged and the water droplets negatively charged in the cloud?

Q.

Which of the following is correct about wool?

1. Insulator

2. Radiator

3. Conductor

4. Wool melts on heating

Q. Every liquid, when taken in a container, has the property that, its free surface behaves like a stretched membrane with a tendency to contract and acquire the _______ surface area.

1. Maximum
2. Minimum
3. None of these
4. Infinite

Q. What are the factors affecting the surface tension of a liquid?

Q.

45. A gas fills its container completely. Why?

Q. A solid exerts pressure _____ on/to its base

1. upwards
2. sidewards
3. downwards
4. parallel

Q.

People tell that if a person swimming in river, sea, or pool swallow water they will start drowning. Is it true? If yes then how?

Q.

Liquids and gases are called ......

Q.

47. Compare the properties of solids, liquids and gases in tabular form.

Q. A cubic vessel of height 1m is full of water. Minimum work done in taking water out from vessel will be?

Q. ntCalculate the Ksp of sparingly soluble salt XY2(s) at 25 degree celcius, if the vapour pressure of its saturated solution in water is 31.78 mm of Hg and vapour pressure of pure water is 31.82 mm of Hg?n

Q. An annular disc of radii $r_1=10cm$ and $r_2=5cm$ is placed on a water surface. Find the surface tension force on the
disc if we want to pull it form the water surface. Take the coefficient of surface tension $=g=10m{s}^{-2}$.

1. $6782.4$ dyne
2. $67.82$ dyne
3. none of these
4. $678.24$ dyne

Q. A chain of length $L$ and mass $M$ is hanging by fixing its upper end to a rigid support. The tension in the chain at a distance $x$ from the rigid support is :

1. zero
2. $F$
3. $Mg\frac{(L-x)}{L}$
4. $Mg\frac{x}{L}$

Q. The work done in breaking a spherical drop of a liquid (surface tension T) of radius R into 8 equal drops is

1. $\pi$$R^{2}T$
2. $2\pi$$R^{2}T$
3. $16\pi$$R^{2}T$
4. $4\pi$$R^{2}T$

Q. A man is sitting in a boat which is floating in a pond. If the man drinks some water from the pond, water level in the pond decreases.

1. True
2. False

Q. A car with closed windows takes a left turn. A helium balloon in the car will be pushed to the :

1. Right
2. Left
3. Front
4. will not be pushed

Q. A cylindrical block of 314N is exerting a pressure of 200Pa then find the circumference of the circular part of the cylinder.

Q. A square wire frame of side 10 cm is dipped in a liquid of surface tension 28 x ${10}^{-3}N{m}^{-1}$. On taking out, a membrane is formed. What is the force acting on the surface of wire frame?

Q. Choose the word/phrase which is opposite in meaning to the bold word/phrase in the sentence.
He has a delicate constitution.

1. fit
2. ungainly
3. strong
4. rugged

Q.

Mosquitoes can stand on water due to

1. attraction between feet and water

2. elastic tension

3. surface tension

4. strong feet

Q.

The meniscus of water is

1. convex

2. plane

3. concave

4. none of the above