02. Capillary and Angle of Contact
Mechanical Properties of Fluids

143009 A long glass capillary tube is dipped in water. It is known that water wets glass. The water level rises by $h$ in the tube. The tube is now pushed down so that only a length $h / 2$ is outside the water surface. The angle of contact at the water surface at the upper end of the tube will be

1 $\tan _{2}^{-1}$
2 $60^{\circ}$
3 $30^{\circ}$
4 $15^{\circ}$
Mechanical Properties of Fluids

143010 A vessel, whose bottom has found holes with diameter of $1 \mathrm{~mm}$ is filled with water. Assuming that surface tension acts only at holes, then the maximum height to which the water can be filled in vessel without leakage is

1 $3 \mathrm{~cm}$
2 $0.3 \mathrm{~cm}$
3 $3 \mathrm{~mm}$
4 $3 \mathrm{~m}$
(Surface tension of water is $75 \times 10^{-3} \mathrm{~N} / \mathrm{m}$ and $\mathrm{g}$ $=10 \mathrm{~m} / \mathrm{s}^{2}$ )
Mechanical Properties of Fluids

143011 Three liquids of densities $\rho_{1}, \rho_{2}$ and $\rho_{3}$ (with $\rho_{1}$ $>\rho_{2}>\rho_{3}$, having the same value of surface tension $T$, rise to the same height in three identical capillaries. The angles of contact $\theta_{1}, \theta_{2}$ and $\theta_{3}$ obey

1 $\frac{\pi}{2}>\theta_{1}>\theta_{2}>\theta_{3} \geq 0$
2 $0 \leq \theta_{1} \lt \theta_{2} \lt \theta_{3} \lt \frac{\pi}{2}$
3 $\frac{\pi}{2} \lt \theta_{1} \lt \theta_{2} \lt \theta_{3} \lt \pi$
4 $\pi>\theta_{1}>\theta_{2}>\theta_{3}>\frac{\pi}{2}$
Mechanical Properties of Fluids

142939 Water rises in a glass capillary tube due to

1 surface tension of water
2 cohesive force of glass molecules
3 temperature of water
4 adhesive force between water molecules and the walls of the glass tube
Mechanical Properties of Fluids

142965 Which one of following statements about the angle of contact $(\theta)$, is wrong ?

1 $\theta>0^{\circ}$ for pure water - glass pair.
2 $\theta$ is not constant for particular solid - liquid pair.
3 $\theta \lt 90^{\circ}$ for kerosene - glass pair.
4 $\theta>90^{\circ}$ for mercury - glass pair.
Mechanical Properties of Fluids

143009 A long glass capillary tube is dipped in water. It is known that water wets glass. The water level rises by $h$ in the tube. The tube is now pushed down so that only a length $h / 2$ is outside the water surface. The angle of contact at the water surface at the upper end of the tube will be

1 $\tan _{2}^{-1}$
2 $60^{\circ}$
3 $30^{\circ}$
4 $15^{\circ}$
Mechanical Properties of Fluids

143010 A vessel, whose bottom has found holes with diameter of $1 \mathrm{~mm}$ is filled with water. Assuming that surface tension acts only at holes, then the maximum height to which the water can be filled in vessel without leakage is

1 $3 \mathrm{~cm}$
2 $0.3 \mathrm{~cm}$
3 $3 \mathrm{~mm}$
4 $3 \mathrm{~m}$
(Surface tension of water is $75 \times 10^{-3} \mathrm{~N} / \mathrm{m}$ and $\mathrm{g}$ $=10 \mathrm{~m} / \mathrm{s}^{2}$ )
Mechanical Properties of Fluids

143011 Three liquids of densities $\rho_{1}, \rho_{2}$ and $\rho_{3}$ (with $\rho_{1}$ $>\rho_{2}>\rho_{3}$, having the same value of surface tension $T$, rise to the same height in three identical capillaries. The angles of contact $\theta_{1}, \theta_{2}$ and $\theta_{3}$ obey

1 $\frac{\pi}{2}>\theta_{1}>\theta_{2}>\theta_{3} \geq 0$
2 $0 \leq \theta_{1} \lt \theta_{2} \lt \theta_{3} \lt \frac{\pi}{2}$
3 $\frac{\pi}{2} \lt \theta_{1} \lt \theta_{2} \lt \theta_{3} \lt \pi$
4 $\pi>\theta_{1}>\theta_{2}>\theta_{3}>\frac{\pi}{2}$
Mechanical Properties of Fluids

142939 Water rises in a glass capillary tube due to

1 surface tension of water
2 cohesive force of glass molecules
3 temperature of water
4 adhesive force between water molecules and the walls of the glass tube
Mechanical Properties of Fluids

142965 Which one of following statements about the angle of contact $(\theta)$, is wrong ?

1 $\theta>0^{\circ}$ for pure water - glass pair.
2 $\theta$ is not constant for particular solid - liquid pair.
3 $\theta \lt 90^{\circ}$ for kerosene - glass pair.
4 $\theta>90^{\circ}$ for mercury - glass pair.
Mechanical Properties of Fluids

143009 A long glass capillary tube is dipped in water. It is known that water wets glass. The water level rises by $h$ in the tube. The tube is now pushed down so that only a length $h / 2$ is outside the water surface. The angle of contact at the water surface at the upper end of the tube will be

1 $\tan _{2}^{-1}$
2 $60^{\circ}$
3 $30^{\circ}$
4 $15^{\circ}$
Mechanical Properties of Fluids

143010 A vessel, whose bottom has found holes with diameter of $1 \mathrm{~mm}$ is filled with water. Assuming that surface tension acts only at holes, then the maximum height to which the water can be filled in vessel without leakage is

1 $3 \mathrm{~cm}$
2 $0.3 \mathrm{~cm}$
3 $3 \mathrm{~mm}$
4 $3 \mathrm{~m}$
(Surface tension of water is $75 \times 10^{-3} \mathrm{~N} / \mathrm{m}$ and $\mathrm{g}$ $=10 \mathrm{~m} / \mathrm{s}^{2}$ )
Mechanical Properties of Fluids

143011 Three liquids of densities $\rho_{1}, \rho_{2}$ and $\rho_{3}$ (with $\rho_{1}$ $>\rho_{2}>\rho_{3}$, having the same value of surface tension $T$, rise to the same height in three identical capillaries. The angles of contact $\theta_{1}, \theta_{2}$ and $\theta_{3}$ obey

1 $\frac{\pi}{2}>\theta_{1}>\theta_{2}>\theta_{3} \geq 0$
2 $0 \leq \theta_{1} \lt \theta_{2} \lt \theta_{3} \lt \frac{\pi}{2}$
3 $\frac{\pi}{2} \lt \theta_{1} \lt \theta_{2} \lt \theta_{3} \lt \pi$
4 $\pi>\theta_{1}>\theta_{2}>\theta_{3}>\frac{\pi}{2}$
Mechanical Properties of Fluids

142939 Water rises in a glass capillary tube due to

1 surface tension of water
2 cohesive force of glass molecules
3 temperature of water
4 adhesive force between water molecules and the walls of the glass tube
Mechanical Properties of Fluids

142965 Which one of following statements about the angle of contact $(\theta)$, is wrong ?

1 $\theta>0^{\circ}$ for pure water - glass pair.
2 $\theta$ is not constant for particular solid - liquid pair.
3 $\theta \lt 90^{\circ}$ for kerosene - glass pair.
4 $\theta>90^{\circ}$ for mercury - glass pair.
Mechanical Properties of Fluids

143009 A long glass capillary tube is dipped in water. It is known that water wets glass. The water level rises by $h$ in the tube. The tube is now pushed down so that only a length $h / 2$ is outside the water surface. The angle of contact at the water surface at the upper end of the tube will be

1 $\tan _{2}^{-1}$
2 $60^{\circ}$
3 $30^{\circ}$
4 $15^{\circ}$
Mechanical Properties of Fluids

143010 A vessel, whose bottom has found holes with diameter of $1 \mathrm{~mm}$ is filled with water. Assuming that surface tension acts only at holes, then the maximum height to which the water can be filled in vessel without leakage is

1 $3 \mathrm{~cm}$
2 $0.3 \mathrm{~cm}$
3 $3 \mathrm{~mm}$
4 $3 \mathrm{~m}$
(Surface tension of water is $75 \times 10^{-3} \mathrm{~N} / \mathrm{m}$ and $\mathrm{g}$ $=10 \mathrm{~m} / \mathrm{s}^{2}$ )
Mechanical Properties of Fluids

143011 Three liquids of densities $\rho_{1}, \rho_{2}$ and $\rho_{3}$ (with $\rho_{1}$ $>\rho_{2}>\rho_{3}$, having the same value of surface tension $T$, rise to the same height in three identical capillaries. The angles of contact $\theta_{1}, \theta_{2}$ and $\theta_{3}$ obey

1 $\frac{\pi}{2}>\theta_{1}>\theta_{2}>\theta_{3} \geq 0$
2 $0 \leq \theta_{1} \lt \theta_{2} \lt \theta_{3} \lt \frac{\pi}{2}$
3 $\frac{\pi}{2} \lt \theta_{1} \lt \theta_{2} \lt \theta_{3} \lt \pi$
4 $\pi>\theta_{1}>\theta_{2}>\theta_{3}>\frac{\pi}{2}$
Mechanical Properties of Fluids

142939 Water rises in a glass capillary tube due to

1 surface tension of water
2 cohesive force of glass molecules
3 temperature of water
4 adhesive force between water molecules and the walls of the glass tube
Mechanical Properties of Fluids

142965 Which one of following statements about the angle of contact $(\theta)$, is wrong ?

1 $\theta>0^{\circ}$ for pure water - glass pair.
2 $\theta$ is not constant for particular solid - liquid pair.
3 $\theta \lt 90^{\circ}$ for kerosene - glass pair.
4 $\theta>90^{\circ}$ for mercury - glass pair.
Mechanical Properties of Fluids

143009 A long glass capillary tube is dipped in water. It is known that water wets glass. The water level rises by $h$ in the tube. The tube is now pushed down so that only a length $h / 2$ is outside the water surface. The angle of contact at the water surface at the upper end of the tube will be

1 $\tan _{2}^{-1}$
2 $60^{\circ}$
3 $30^{\circ}$
4 $15^{\circ}$
Mechanical Properties of Fluids

143010 A vessel, whose bottom has found holes with diameter of $1 \mathrm{~mm}$ is filled with water. Assuming that surface tension acts only at holes, then the maximum height to which the water can be filled in vessel without leakage is

1 $3 \mathrm{~cm}$
2 $0.3 \mathrm{~cm}$
3 $3 \mathrm{~mm}$
4 $3 \mathrm{~m}$
(Surface tension of water is $75 \times 10^{-3} \mathrm{~N} / \mathrm{m}$ and $\mathrm{g}$ $=10 \mathrm{~m} / \mathrm{s}^{2}$ )
Mechanical Properties of Fluids

143011 Three liquids of densities $\rho_{1}, \rho_{2}$ and $\rho_{3}$ (with $\rho_{1}$ $>\rho_{2}>\rho_{3}$, having the same value of surface tension $T$, rise to the same height in three identical capillaries. The angles of contact $\theta_{1}, \theta_{2}$ and $\theta_{3}$ obey

1 $\frac{\pi}{2}>\theta_{1}>\theta_{2}>\theta_{3} \geq 0$
2 $0 \leq \theta_{1} \lt \theta_{2} \lt \theta_{3} \lt \frac{\pi}{2}$
3 $\frac{\pi}{2} \lt \theta_{1} \lt \theta_{2} \lt \theta_{3} \lt \pi$
4 $\pi>\theta_{1}>\theta_{2}>\theta_{3}>\frac{\pi}{2}$
Mechanical Properties of Fluids

142939 Water rises in a glass capillary tube due to

1 surface tension of water
2 cohesive force of glass molecules
3 temperature of water
4 adhesive force between water molecules and the walls of the glass tube
Mechanical Properties of Fluids

142965 Which one of following statements about the angle of contact $(\theta)$, is wrong ?

1 $\theta>0^{\circ}$ for pure water - glass pair.
2 $\theta$ is not constant for particular solid - liquid pair.
3 $\theta \lt 90^{\circ}$ for kerosene - glass pair.
4 $\theta>90^{\circ}$ for mercury - glass pair.