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 

1. H

2. 2H

3. 7H

4. 8H

Due to capillary action, a liquid will rise in a tube, if the angle of contact is

1. acute

2. obtuse

3. 90^o

4. zero

Two capillary tubes P and Q are dipped in water. The height of water level in capillary P is 2/3 to the height in Q capillary. The ratio of their diameters is

1. 2: 3

2. 3: 2

3. 3: 4

4. 4: 3

The value of coefficient of volume expansion of glycerin is $5\times {10}^{-4} {\mathrm{K}}^{-1}$. The fractional charge in the density of glycerin for a rise of $40° \mathrm{C}$ in its temperature is

1. 0.020

2. 0.025

3. 0.010

4. 0.015

Which one of the following would a hydrogen balloon find easiest to lift ?

1. 1 kg of steet

2. 1 kg of water

3. 1 kg of lightly packed feathers

4. All the same.

Blood is flowing at the rate of 200 ${\mathrm{cm}}^3{\mathrm{s}}^{-1}$ in a capilarry of cross sectional area $0.5 {\mathrm{m}}^2$. The velocity of flow, in ${\mathrm{mms}}^{-1}$, is

1. 0.1

2. 0.2

3. 0.3

4. 0.4

An ornament made of silver is suspected to be hollow. It weighs 288.75 gm in air. It can displace 30 cc of water. If the specific gravity of silver is 10.5 . The volume of cavity is

1. 2.5 cc

2. 3 cc

3. 5 cc

4. 7.5 cc

  Two soap bubbles of radii ${\mathrm{r}}_{\mathrm{a}} \mathrm{and} {\mathrm{r}}_2, {\mathrm{r}}_1>{\mathrm{r}}_2$ get attached to each other to have a common interface. The radius of this interface is

1. ${\mathrm{r}}_1-{\mathrm{r}}_2$

2. ${\mathrm{r}}_1+{\mathrm{r}}_2$

3. $\frac{{\mathrm{r}}_1{\mathrm{r}}_2}{{\mathrm{r}}_1+{\mathrm{r}}_2}$

4. $\frac{{\mathrm{r}}_1{\mathrm{r}}_2}{\mathrm{r}-{\mathrm{r}}_2}$

In the figure shown.

1. p₁ > p₀

2. p > p₀

3. p = p₀

4. p = 0

A large number of liquid drops each of radius r coalesce to form a single drop of radius R. The energy released in the process is converted into the kinetic energy of the big drop so formed. The speed of the big drop is(given surface tension of liquid is T, density of liquid is $\rho$)

1. $\sqrt{\frac{\mathrm{T}}{\mathrm{\rho }}\left(\frac{1}{\mathrm{r}}-\frac{1}{\mathrm{R}}\right)}$

2. $\sqrt{\frac{2\mathrm{T}}{\mathrm{\rho }}\left(\frac{1}{\mathrm{r}}-\frac{1}{\mathrm{R}}\right)}$

3. $\sqrt{\frac{4\mathrm{T}}{\mathrm{\rho }}\left(\frac{1}{\mathrm{r}}-\frac{1}{\mathrm{R}}\right)}$

4. $\sqrt{\frac{6\mathrm{T}}{\mathrm{\rho }}\left(\frac{1}{\mathrm{r}}-\frac{1}{\mathrm{R}}\right)}$