A metal block of area \(0.10~\text{m}^{2}\) is connected to a \(0.010\) kg mass via a string that passes over an ideal pulley (considered massless and frictionless), as in the figure below. A liquid film with a thickness of \(0.30\) mm is placed between the block and the table. When released the block moves to the right with a constant speed of \(0.085\) m/s. The coefficient of viscosity of the liquid is:
1. \(4.45 \times 10^{-2}~\text{Pa-s}\)
2. \(4.45 \times 10^{-3}~\text{Pa-s}\)
3. \(3.45 \times 10^{-2}~\text{Pa-s}\)
4. \(3.45 \times 10^{-3}~\text{Pa-s}\)
(a) | gases decrease. | (b) | liquids increase. |
(c) | gases increase. | (d) | liquids decrease. |
Which of the following diagrams does not represent a streamline flow?
1. | 2. | ||
3. | 4. |
A tank has an orifice near its bottom. The volume of the liquid flowing per second out of the orifice does not depend upon:
1. | the area of the orifice. | 2. | the height of the liquid level above the orifice. |
3. | the density of the liquid. | 4. | acceleration due to gravity. |
Water rises to height h in a capillary tube. If the length of the capillary tube above the surface of water is made less than h, then:
1. | water does not rise at all. |
2. | water rises up to the top of the capillary tube, then starts overflowing like a fountain. |
3. | water rises up to the top of the capillary tube and stays there without overflowing. |
4. | water rises up to a point a little below the top and stays there. |
The wettability of a surface by a liquid depends primarily on:
1. | viscosity |
2. | surface tension |
3. | density |
4. | angle of contact between the surface and the liquid |
Assertion (A): | When height of a tube is less than liquid rise in the capillary tube, the liquid does not overflow. |
Reason (R): | Product of radius of meniscus and height of liquid in capillary tube always remains constant. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | (A) is False but (R) is True. |
Assertion (A): | Specific gravity of a fluid is a dimensionless quantity. |
Reason (R): | It is the ratio of the density of the fluid to the density of water. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | Both (A) and (R) are False. |
Assertion (A): | A piece of ice floats in water, the level of water remains unchanged when the ice melts completely. |
Reason (R): | According to Archimedes principle, the loss in weight of the body in the liquid is equal to the weight of the liquid displaced by the immersed part of the body. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | Both (A) and (R) are False. |
Two small spherical metal balls, having equal masses, are made from materials of densities \(\rho_1\) and \(\rho_2\) such that and having radii of \(1\) mm and \(2\) mm, respectively. They are made to fall vertically (from rest) in a viscous medium whose coefficient of viscosity equals and whose density is \(0.1\). The ratio of their terminal velocities would be:
1. | 2. | ||
3. | 4. |