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