Buoyancy and floatation MCQ Questions- Mechanicaltalks February 9, 2022 by Randeep Paramanik 0 Created on February 09, 2022 Buoyancy and floatation 1 / 25 A student wants to find the absolute pressure of water at a point below the surface of water. He has a barometer and a manometer pressure gauge. The barometer reads 1.3152 bar where as the manometer pressure gauge reads 0.3152 bar. What is the absolute pressure? (Assume that pressure at one end of the manometer is atmospheric.) 1 bar 1.3152 bar 1.6304 bar 0.3152 bar 2 / 25 A simple U-tube manometer can measure negative gauge pressures. False True 3 / 25 The principle of floatation of bodies is based on the premise of Metacentre Newtons first law Newtons law of viscosity None of the mentioned 4 / 25 How can relatively denser object be made to float on the less dense fluid? By altering the shape. None of the mentioned By altering the shear forces acting on the object By altering the forces acting on the object 5 / 25 In case of spherically shaped bodies of uniform mass distribution and completely immersed in fluid and floating, the centre of buoyancy coincides with centre of gravity. False True 6 / 25 For a completely immersed body, the metacentric height is always zero. True False 7 / 25 Which of the following cannot be the value of absolute pressure of a fluid at any point? 200 bar – 1 bar 1.013 bar 0 8 / 25 A body of dimensions 2.7 m * 3.8 m * 2.5 m, weighs 2500 N in water.Find its weight in air. 101.65 kN 508.25 kN 127.06 kN 254.12 kN 9 / 25 A stone weighs 450 N in air and 200 N in water. Compute the volume of stone. .075 m3 .05 m3 .025 m3 None of the mentioned 10 / 25 The floating body is said to be in neutral equilibrium if the metacentre is above the centre of gravity. True False 11 / 25 In a stationary fluid, how does the local pressure of the fluid vary? In the horizontal direction only Neither with depth nor along horizontal direction Both with depth and along horizontal direction With depth only 12 / 25 What is the principal cause of action of buoyant force on a body submerged partially or fully in fluid? Displacement of fluid due to submerged body None of the mentioned Internal shear forces mitigating external forces Development of force due to dynamic action 13 / 25 Find the position of centre of buoyancy for a wooden block of width 3.5 m and depth 1 m, when it floats horizontally in water. The density of wooden block id 850 kg/m3 and its length 7.0 m. 1.65 0.85 1.05 0.95 14 / 25 Submarines use principle of ‘neutral buoyancy’ to go into the water. True False 15 / 25 As a balloon rises in the air its volume increases, at the end it acquires a stable height and cannot rise any further. False True 16 / 25 When body is completely or partially immersed in a fluid, how much its weight be distributed for it to be in stable equilibrium. Around the lower part Is independent of weight distribution None of the mentioned. Around the upper part 17 / 25 In stable equilibrium for completely submerged bodies what is the relation between forces? Buoyancy force < Weight of body Buoyancy force=Weight of body, the centre of buoyancy is above the centre of gravity. None of the mentioned. Buoyancy force= Weight of body,the centre of buoyancy is below the centre of gravity. 18 / 25 If the magnitude of dimension of a rectangular wooden block is length>breadth>height, then for it to float on the water, it should be immersed in what manner? It should be immersed such that height is partially immersed None of the mentioned. It should be immersed vertically such that length is partially immersed It should be immersed horizontally such that breadth is partially immersed 19 / 25 A uniform body of size 4 m long, 2.5 m wide and 1.5 m deep floats in water. What is the weight of the body if depth of immersion is 1 m ? 294.3 kN 588.6 kN 147.1 kN 73.5 kN 20 / 25 A manometric liquid should suitably have Low density & Low Vapour pressure High density & High Vapour pressure Low density & High Vapour pressure High density & Low Vapour pressure 21 / 25 What happens to the buoyant force acting on the airship as it rises in the air? Buoyant force remains constant Buoyant force increases Buoyant force first increases then shows decrease Buoyant force decreases 22 / 25 Proper explanation for metacentre is: All of the mentioned. Point at which line of action of force meets the normal axis of body when it is given angular displacement point about which body starts oscillating when it is given small angular displacement Intersection of line passing through new centre of buoyancy and centre of gravity. 23 / 25 The floating body is said to be in stable equilibrium if the metacentre is below the centre of gravity. False. True 24 / 25 Both ends of a U-tube manometer are exposed to the atmosphere. There exists a possibility that the height difference of the manometer is non-zero. True or False? True False 25 / 25 A stone weighs 650 N in air and 275 N in water. Compute its specific gravity. 3.46 1.73 2.45 0.865 Your score isThe average score is 0% LinkedIn Facebook Twitter VKontakte 0% Restart quiz Related Spread the love