The radii of two soap bubbles are ${\mathrm{r}}_{1}$ and ${\mathrm{r}}_{2}$ . In isothermal conditions, two meet together in vaccum. Then the radius of the resultant bubble is given by

(a) $\mathrm{R}=\left({\mathrm{r}}_{1}+{\mathrm{r}}_{2}\right)/2$                    (b) $\mathrm{R}={\mathrm{r}}_{1}\left({\mathrm{r}}_{1}{\mathrm{r}}_{2}+{\mathrm{r}}_{2}\right)$

(c) ${\mathrm{R}}^{2}={\mathrm{r}}_{1}^{2}+{\mathrm{r}}_{2}^{2}$                         (d) $\mathrm{R}={\mathrm{r}}_{1}+{\mathrm{r}}_{2}$

Concept Questions :-

Surface tension

Difficulty Level:

When a large bubble rises from the bottom of a lake to the surface, its radius doubles. If atmospheric pressure is equal to that of column of water height H, then the depth of lake is

(a) H                                  (b) 2H
(c) 7H                                (d) 8H

Concept Questions :-

Pressure
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

Excess pressure of one soap bubble is four times more than the other. Then the ratio of volume of first bubble to another one is
(a) 1 : 64                    (b) 1 : 4
(c) 64 : 1                    (d) 1 : 2

Concept Questions :-

Surface tension
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

There are two liquid drops of different radii. The excess pressure inside over the outside is

(a) More in the big drop

(b) More in the small drop

(c) Equal in both drops

(d) There is no excess pressure inside the drops

Concept Questions :-

Surface tension
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

If pressure at half the depth of a lake is equal to 2/3 pressure at the bottom of the lake then what is the depth of the lake

(a) 10m                 (b) 20m
(c) 60m                 (d) 30m

Concept Questions :-

Pressure
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

If the radius of a soap bubble is four times that of another, then the ratio of their pressures will be

(a) 1 : 4                                 (b) 4 : 1
(c) 16 : 1                               (d) 1 : 16

Concept Questions :-

Surface tension
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

A spherical drop of water has radius 1 mm If surface tension of water is $70×{10}^{-3}$ N/m difference of pressures between inside and out side of the spherical drop is

(a)                            (b)
(c)                           (d) Zero

Concept Questions :-

Surface tension
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

In capillary tube, pressure below the curved surface of water will be

(a) Equal to atmospheric

(b) Equal to upper side pressure

(c) More than upper side pressure

(d) Lesser than upper side pressure

Concept Questions :-

Capillary rise

Difficulty Level:

The pressure inside a small air bubble of radius 0.1 mm situated just below the surface of water will be equal to
[Take surface tension of water  and atmospheric pressure = ]

(a)             (b)

(c)             (d)

Concept Questions :-

Surface tension
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

Two bubbles A and B are joined through a narrow tube where bubble A is bigger. Then

1. The size of A will increase

2. The size of B will increase

3. The size of B will increase until the pressure equals

4. None of these

Concept Questions :-

Surface tension