A square plate of 0.1 m side moves parallel to a second plate with a velocity of 0.1 m/s, both plates being immersed in water. If the viscous force is 0.002 N and the coefficient of viscosity is 0.01 poise, then the distance between the plates in m is:
1. | 0.1 | 2. | 0.05 |
3. | 0.005 | 4. | 0.0005 |
A spherical ball of radius \(r\) is falling in a viscous fluid of viscosity \(\eta\) with a velocity \(v.\) The retarding viscous force acting on the spherical ball is:
1. | inversely proportional to \(r\) but directly proportional to velocity \(v.\) |
2. | directly proportional to both radius \(r\) and velocity \(v.\) |
3. | inversely proportional to both radius \(r\) and velocity \(v.\) |
4. | directly proportional to \(r\) but inversely proportional to \(v.\) |
The pans of a physical balance are in equilibrium. If Air is blown under the right hand pan then the right hand pan will:
1. | Move up | 2. | Move down |
3. | Move erratically | 4. | Remain at the same level |
A sniper fires a rifle bullet into a gasoline tank making a hole 53.0 m below the surface of gasoline. The tank was sealed at 3.10 atm. The stored gasoline has a density of 660 . The velocity with which gasoline begins to shoot out of the hole will be:
1. | 27.8 ms-1 | 2. | 41.0 ms-1 |
3. | 9.6 ms-1 | 4. | 19.7 ms-1 |
A tank is filled with water up to a height \(\mathrm H.\) Water is allowed to come out of a hole \(\mathrm P\) in one of the walls at a depth \(\mathrm D\) below the surface of water. Express the horizontal distance \(\mathrm{x}\) in terms of \(\mathrm H\) and \(\mathrm {D}\text :\)
1.
2.
3.
4.
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 block of ice floats on a liquid of density 1.2 in a beaker. The level of liquid when ice completely melts-
1. Remains same
2. Rises
3. Lowers
4. (1), (2) or (3)
In order to float a ring of area 0.04 in a liquid of surface tension 75 N/m, the required surface energy will be:
1. | 3 J | 2. | 6.5 J |
3. | 1.5 J | 4. | 4 J |
If pressure at half the depth of a lake is equal to 2/3rd the pressure at the bottom of the lake, then the depth of the lake is:
1. | 10 m | 2. | 20 m |
3. | 60 m | 4. | 30 m |
A spherical drop of water has a radius of 1 mm. If the surface tension of water is N/m, the difference in pressures inside and outside the spherical drop is:
1. | 35 N / m2 | 2. | 70 N / m2 |
3. | 140 N / m2 | 4. | Zero |