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.
A small spherical solid ball is dropped in a viscous liquid. Its journey in the liquid is best described in the figure by:
1. | curve A | 2. | curve B |
3. | curve C | 4. | curve D |
A small tiny water droplet is falling towards earth at a uniform speed of 1 cm/s. When 27 such identical droplets combine together to form a bigger drop, then with what uniform velocity will this bigger drop fall?
1. 27 cm/s
2. 9 cm/s
3. 3 cm/s
4. 81 cm/s
If a small drop of water falls from rest through a large height h in air, then the final velocity is:
1. | \(\propto \sqrt{\mathrm{h}}\) |
2. | \(\propto \mathrm{h} \) |
3. | \(\propto(1 / h)\) |
4. | Almost independent of h |
A small sphere of radius \(r\) falls from rest in a viscous liquid. As a result, heat is produced due to the viscous force. The rate of production of heat when the sphere attains its terminal velocity is proportional to:
1. \(r^3\)
2. \(r^2\)
3. \(r^5\)
4. \(r^4\)
An iron sphere is dropped into a viscous liquid. Which of the following represents its acceleration (a) versus time (t) graph?
1. | 2. | ||
3. | 4. |