EASY

Earn 100

A soap bubble contains two surface layers, what is the excess pressure just inside the first layer when seen from outside the bubble?

50% studentsanswered this correctly

Important Questions on Properties of Matter

MEDIUM

Physics>Mechanics>Properties of Matter>Surface Tension

A large number of water drops, each of radius

r

, combine to have a drop of radius

R

. If the surface tension is

T

and mechanical equivalent of heat is

J

, the rise in heat energy per unit volume will be:

MEDIUM

Physics>Mechanics>Properties of Matter>Surface Tension

A soap bubble, blown by a mechanical pump at the mouth of a tube increases in volume with time at a constant rate. The graph that correctly depicts the time dependence of pressure inside the bubble is given by:

EASY

Physics>Mechanics>Properties of Matter>Surface Tension

Two separate soap bubbles of radii

3 \times 10^{- 3} m

and

2 \times 10^{- 3} m

respectively, formed of same liquid (surface tension

65 \times 10^{- 2} N m^{- 1}

) come together to form a double bubble. The radius of interface of double bubble is

HARD

Physics>Mechanics>Properties of Matter>Surface Tension

Two spherical soap bubbles of radii

r_{1}

and

r_{2}

in vacuum combine under isothermal conditions. The resulting bubble has a radius equal to:

EASY

Physics>Mechanics>Properties of Matter>Surface Tension

Two soap bubbles of radii

3 mm

and

4 mm

confined in vacuum coalesce isothermally to form a new bubble. The radius of the bubble formed

(in mm)

MEDIUM

Physics>Mechanics>Properties of Matter>Surface Tension

A boy formed a bubble and a liquid drop form the same soapy water. The pressure difference between inside and outside of the soap bubble is measured to be

100 N / m^{2} .

If the radius of the droplet is half of the radius of the bubble, then the pressure difference between the inside and outside of the droplet is

EASY

Physics>Mechanics>Properties of Matter>Surface Tension

Pressure inside two soap bubbles are

1.01

and

1.02

atmosphere, respectively. The ratio of their volumes is :

MEDIUM

Physics>Mechanics>Properties of Matter>Surface Tension

Two spherical soap bubbles of radii

R_{1}

and

R_{2}

combine under isothermal condition to form a single bubble. The radius of the resultant bubble is

EASY

Physics>Mechanics>Properties of Matter>Surface Tension

A glass capillary tube is of the shape of a truncated cone with an apex angle

α

so that its two ends have cross-sections of different radii. When dipped in water vertically, the water rises in it to a height

h

, where the radius of its cross-section is

b

. If the surface tension of water is

S

, its density is

ρ

, and its contact angle with glass is

θ

, then the value of

h

will be (

g

is the acceleration due to gravity)

Question Image

EASY

Physics>Mechanics>Properties of Matter>Surface Tension

A soap bubble having radius of

1 m m

is blown from a detergent solution having a surface tension of

2.5 \times 10^{- 2} N m^{- 1} .

The pressure inside the bubble equals at a point

Z_{0}

below the free surface of water in a container. Taking

g = 10 m s^{- 2},

density of water

= 10^{3} k g m^{- 3},

the value of

Z_{0}

MEDIUM

Physics>Mechanics>Properties of Matter>Surface Tension

64 identical water droplets combine to form a large drop. Find the ratio of the total surface energy of 64 droplets to that of the large drop.

HARD

Physics>Mechanics>Properties of Matter>Surface Tension

A small soap bubble of radius 4cm is trapped inside another bubble of radius 6cm without any contact. Let

P_{2}

be the pressure inside the inner bubble and

P_{0}

, the pressure outside the outer bubble. Radius of another bubble with pressure difference

P_{2} - P_{0}

between its inside and outside would be:

MEDIUM

Physics>Mechanics>Properties of Matter>Surface Tension

A soap bubble of radius

3 cm

is formed inside another soap bubble of radius,

6 cm

. The radius of an equivalent soap bubble that has the same excess pressure as inside the smaller bubble with respect to the atmospheric pressure is____

cm .

MEDIUM

Physics>Mechanics>Properties of Matter>Surface Tension

Suppose you have taken a dilute solution of oleic acid in such a way that its concentration becomes

0.01 {cm}^{3}

of oleic acid per

{cm}^{3}

of the solution. Then you make a thin film of this solution (monomolecular thickness) of area

4 {cm}^{2}

by considering

100

spherical drops of radius

{(\frac{3}{40 π})}^{\frac{1}{3}} \times 10^{- 3} cm .

Then the thickness of oleic acid layer will be

x \times 10^{- 14} m

. Where

x

is ________ .

EASY

Physics>Mechanics>Properties of Matter>Surface Tension

Two soap bubbles of radii,

R

and,

2 R

(in vacuum) coalesce under isothermal conditions. The radius of the new bubble is (surface tension of soap solution is

2.5 \times 10^{- 2} N m^{- 1}

)

HARD

Physics>Mechanics>Properties of Matter>Surface Tension

A water drop of radius $1 cm$ is broken into $729$ equal droplets. If surface tension of water is $75 dyne {cm}^{- 1}$ , then the gain in surface energy upto first decimal place will be

[Given $π = 3.14$ ]

EASY

Physics>Mechanics>Properties of Matter>Surface Tension

If a soap bubble expands, the pressure inside the bubble

HARD

Physics>Mechanics>Properties of Matter>Surface Tension

A certain number of spherical drops of a liquid of radius

r

coalesce to form a single drop of radius

R

and volume

V .

T

is the surface tension of the liquid then:

MEDIUM

Physics>Mechanics>Properties of Matter>Surface Tension

A big water drop is formed by the combination of

n

small water drops of equal radii. The ratio of the surface energy of

n

drops to the surface energy of the big drop is

HARD

Physics>Mechanics>Properties of Matter>Surface Tension

If two glass plates have water between them and are separated by very small distance (see figure), it is very difficult to pull them apart. It is because the water in between forms cylindrical surface on the side that gives rise to lower pressure in the water in comparison to atmosphere. If the radius of the cylindrical surface is R and surface tension of water is T then the pressure in water between the plates is lower by:

Question Image

A soap bubble contains two surface layers, what is the excess pressure just inside the first layer when seen from outside the bubble?

Important Questions on Properties of Matter

Learn and Prepare for any exam you want !