Buoyancy and floatation MCQ Questions- Mechanicaltalks February 9, 2022 by Randeep Paramanik 0 Created on February 09, 2022 Buoyancy and floatation 1 / 25 A stone weighs 650 N in air and 275 N in water. Compute its specific gravity. 3.46 0.865 1.73 2.45 2 / 25 For a completely immersed body, the metacentric height is always zero. False True 3 / 25 Submarines use principle of ‘neutral buoyancy’ to go into the water. True False 4 / 25 Which of the following cannot be the value of absolute pressure of a fluid at any point? 200 bar 1.013 bar 0 – 1 bar 5 / 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.) 0.3152 bar 1.3152 bar 1.6304 bar 1 bar 6 / 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 7 / 25 A manometric liquid should suitably have High density & Low Vapour pressure High density & High Vapour pressure Low density & Low Vapour pressure Low density & High Vapour pressure 8 / 25 As a balloon rises in the air its volume increases, at the end it acquires a stable height and cannot rise any further. True False 9 / 25 A body of dimensions 2.7 m * 3.8 m * 2.5 m, weighs 2500 N in water.Find its weight in air. 127.06 kN 101.65 kN 508.25 kN 254.12 kN 10 / 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 ? 147.1 kN 588.6 kN 294.3 kN 73.5 kN 11 / 25 Proper explanation for metacentre is: All of the mentioned. Intersection of line passing through new centre of buoyancy and centre of gravity. 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 12 / 25 The floating body is said to be in neutral equilibrium if the metacentre is above the centre of gravity. True False 13 / 25 The floating body is said to be in stable equilibrium if the metacentre is below the centre of gravity. True False. 14 / 25 The principle of floatation of bodies is based on the premise of Newtons law of viscosity Newtons first law Metacentre None of the mentioned 15 / 25 In stable equilibrium for completely submerged bodies what is the relation between forces? Buoyancy force=Weight of body, the centre of buoyancy is above the centre of gravity. Buoyancy force= Weight of body,the centre of buoyancy is below the centre of gravity. None of the mentioned. Buoyancy force < Weight of body 16 / 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. True False 17 / 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 vertically such that length is partially immersed It should be immersed horizontally such that breadth is partially immersed It should be immersed such that height is partially immersed None of the mentioned. 18 / 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? False True 19 / 25 What happens to the buoyant force acting on the airship as it rises in the air? Buoyant force remains constant Buoyant force first increases then shows decrease Buoyant force decreases Buoyant force increases 20 / 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 With depth only Both with depth and along horizontal direction 21 / 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 forces acting on the object By altering the shear forces acting on the object 22 / 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 Around the upper part Is independent of weight distribution None of the mentioned. 23 / 25 What is the principal cause of action of buoyant force on a body submerged partially or fully in fluid? None of the mentioned Development of force due to dynamic action Internal shear forces mitigating external forces Displacement of fluid due to submerged body 24 / 25 A simple U-tube manometer can measure negative gauge pressures. False True 25 / 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. 0.95 1.05 0.85 1.65 Your score isThe average score is 0% LinkedIn Facebook VKontakte 0% Restart quiz Related Spread the love