A hemispherical bowl just floats without sinking in a liquid of density . If the outer diameter and the density of the material of the bowl are 1 m and respectively, then the inner diameter of the bowl will be:
1. 0.94 m
2. 0.97 m
3. 0.98 m
4. 0.99 m
A concrete sphere of radius R has a cavity of radius r which is packed with sawdust. The specific gravities of concrete and sawdust are respectively 2.4 and 0.3. For this sphere to float with its entire volume submerged underwater, the ratio of mass of concrete to mass of sawdust will be:
1. | 8 | 2. | 4 |
3. | 3 | 4. | Zero |
A solid sphere of density ( > 1) times lighter than water is suspended in a water tank by a string tied to its base as shown in fig. If the mass of the sphere is m, then the tension in the string is given by:
1.
2.
3.
4.
A boat carrying steel balls is floating on the surface of water in a tank. If the balls are thrown into the tank one by one, how will it affect the level of water?
1. | It will remain unchanged |
2. | It will rise |
3. | It will fall |
4. | First it will first rise and then fall |
A candle of diameter d is floating on a liquid in a cylindrical container of diameter D (D>>d) as shown in figure. If it is burning at the rate of 2cm/hour then the top of the candle will:
1. | Remain at the same height |
2. | Fall at the rate of 1 cm/hour |
3. | Fall at the rate of 2 cm/hour |
4. | Go up at the rate of 1cm/hour |
The velocity of kerosene oil in a horizontal pipe is 5 m/s. If , then the velocity head of oil will be:
1. 1.25 m
2. 12.5 m
3. 0.125 m
4. 125 m
An L-shaped tube with a small orifice is held in a water stream as shown in fig. The upper end of the tube is 10.6 cm above the surface of water. What will be the height of the jet of water coming from the orifice? Velocity of water stream is 2.45 m/s.
1. Zero
2. 20.0 cm
3. 10.6 cm
4. 40.0 cm
An incompressible fluid flows steadily through a cylindrical pipe which has a radius 2r at point A and a radius r at B further along the flow direction. If the velocity at point A is v, its velocity at point B is:
1. 2v
2. v
3. v/2
4. 4v
A wooden block with a coin placed on its top, floats in water as shown in fig. The distance \(l\) and \(h\) are shown there. After some time the coin falls into the water. Then:
1. | \(l\) decreases and \(h\) increases |
2. | \(l\) increases and \(h\) decreases |
3. | Both \(l\) and \(h\) increase |
4. | Both \(l\) and \(h\) decrease |
A wooden stick 2 m long is floating on the surface of the water. The surface tension of water is 0.07 N/m. By putting soap solution on one side of the stick, the surface tension is reduced to 0.06 N/m. The net force on the stick due to surface tension will be:
1. | 0.07 N | 2. | 0.06 N |
3. | 0.01 N | 4. | 0.02 N |