1. In the stability of floating bodies, the stable equilibrium is attained if the meta centre (M) point
______ the centre of gravity (G).
- lies above
- coincides with
- is parallel to
- lies below
Answer: lies above
2. A stone having weights 650 N in the air and 275 N in the water. Find its specific gravity.
- 1.73
- 2.45
- 3.46
- 0.865
Answer: 1.73
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3. A stone having weight of 450 N in the air and 200 N in water. Find the volume of stone.
- 0.025 m3
- 0.05 m3
- 0.075 m3
- None of the above
Answer: 0.025 m3
4. The force of buoyancy depends upon the...
- Weight of the liquid displaced
- Viscosity of liquid
- Compressibility of liquid
- All of the above
Answer: Weight of the liquid displaced
5. The Body floating in the liquid it said to be neutral if it's metacentre is...
- Coincide with the centre of gravity
- Above the centre of gravity
- Below the centre of gravity
- Nice between centre of buoyancy and centre of gravity
Answer: Coincide with the centre of gravity
6. One litre of water occupies volume is...
- 100 cm3
- 250 cm3
- 500 cm3
- 1000 cm3
Answer: 1000 cm3
7. The distance of centre of pressure from free surface of liquid is independent of:
- the density of liquid
- the moment of inertia
- the surface area
- the distance of C.G. from free surface of liquid
Answer: the density of liquid
8. A cuboid of total height = 44 cm, length and breadth = 11 cm each is floating on the water.
What is the height of the cuboid immersed in water if the density of the material is 850
kg/m3 ?
- 74.8 cm
- 37.4 cm
- 30.6 cm
- 20.8 cm
Answer: 37.4 cm
9. The volume of 500 g sealed packet is 250 cm3 . The density of water is 1 g/cm3 . Will the sealed packet sink or float in water?
- The sealed packet remains suspended in water.
- The sealed packet sinks in water.
- The sealed packet floats in water.
- The sealed packet moves around the water.
Answer: The sealed packet sinks in water.
10. The buoyant force acting on the air-ship as it rises in the air will be...
- Buoyant force is increases
- Buoyant force is decreases
- Buoyant force is remains constant
- Buoyant force first increases then decrease
Answer: Buoyant force is decreases
11. The stability of a dam is checked for...
- Tension at the base
- Sliding of the dam
- Overturning of the dam
- All of the above
Answer: All of the above
12. One cubic meter of water weight is...
- 100 lit
- 250 lit
- 500 lit
- 1000 lit
Answer: 1000 lit
13. What percent of the total volume of an iceberg floats above the water surface? Assume the density of ice to be 920 kg/m3 and the density of water to be 1000 kg/m3 .
- 6
- 8
- 92
- 20
Answer: 8
14. A block of iron dropped in a vessel of water, sinks to the bottom. This is because:
- the vessel is not deep enough to allow the block to float.
- the weight of the water displaced by the block is less than the weight of the block.
- the weight of the block is less than the weight of the water displaced by the block.
- the density of water is more than the density of the block.
Answer: the weight of the water displaced by the block is less than the weight of the block.
15. A 16 cm cubical wooden piece along each side floats at the interface between an oil and water with its lowest surface 5 cm below the interface. If the heights of oil and water columns are 12 cm each and density of oil is ρoil is 0.8 g/cc, then calculate the mass of the wooden
piece.
- 1650 g
- 1860 g
- 1500 g
- 3532 g
Answer: 3532 g
16. The denser object is float on the less dense fluid by which method.
- By changing the shape of object
- By altering the forces acting on the object
- By changing the force on the object
- None of the above
Answer: By changing the shape of object
17. The centre of gravity of the volume of a liquid is displaced is called as....
- Centre of pressure
- Centre of buoyancy
- Metacentre
- None of the above
Answer: Centre of buoyancy
18. The volume of a sealed packet is 1 liter and its mass is 800 g. The packet is first put inside the water with a density of 1 g cm-3 and then in another liquid B with a density of 1.5 g cm-3 .
Then which one of the following statements holds true?
- The packet will float in both water and liquid B.
- The packet will sink in both water and liquid B.
- The packet will sink in water but will float in liquid B.
- The packet will float in water and sink in liquid B.
Answer: The packet will float in both water and liquid B
19. Anjana takes two blocks of identical size. One is made of aluminium the other is lead. She submerges them one by one in water. Which of the following statements is true?
- The buoyant force acting on aluminium < Buoyant force on lead
- Buoyant force acting on aluminium > Buoyant force acting on lead
- Buoyant force acting on aluminium = buoyant force acting on lead
- Buoyant force cannot be determined
Answer: Buoyant force acting on aluminium = buoyant force acting on lead
20. When a body is immersed in a fluid, upward force exerted by the fluid is equal to the________.
- volume of water displaced by the body
- density of the Body
- weight of the fluid displaced by the body
- weight of the body
Answer: weight of the fluid displaced by the body
21. An object floats with 14th part of its volume outside the liquid when put in liquid A and 34th part of its volume outside the liquid when put in liquid B. Which of the following statements is true?
- Density of liquid B is greater than density of liquid A.
- The densities of liquid cannot be compared on the basis of above information.
- Density of liquid A is greater than density of liquid B.
- Both liquids have same density.
Answer: Density of liquid B is greater than density of liquid A.
22. Vertical depth of any point below the free surface in a liquid at rest is known as _________ .
- pressure head
- velocity head
- total head
- datum head
Answer: pressure head
23. An object weighing 100 N in the air was found to weight 75 N when fully submerged in water. The relative density of the object is
- 4.0
- 4.5
- 2.5
- 1.125
Answer: 4.0
24. The volume of a small ball is calculated to be 25 cm and it weighs 30 g in air. Will this ball float or sink in water?
- Sink
- Partially sink
- Float
- More than one of the above
Answer: Sink
25. What is the set of ultrafine water particles or ice crystals floating in the air?
- fog
- smog
- cloud
- dew
Answer: cloud
26. The distance of the centre of pressure from the free surface of the liquid is independent of the:
- area exposed to the liquid
- density of liquid
- depth of the centre of gravity from the free surface
- moment of inertia about the centre of gravity
Answer: density of liquid
27. On which of the following factors the magnitude of the buoyant force acting on a body in a given fluid depends?
- Weight of the body immersed in it
- Shape of the body immersed in the fluid.
- Density of the fluid and mass of the body immerse in it
- Density of the fluid and the volume of the body immersed in it
Answer: Density of the fluid and the volume of the body immersed in it