Fluid mechanics multiple choice questions and answers pdf download

For a body floating in a liquid the normal pressure exerted by the liquid acts at a bottom surface of the body b e. Choose the wrong statement a any weight, floating or immersed in a liquid, is acted upon by a buoyant force p Buoyant force is equal to the weight of the liquid displaced c The point through which buoyant force acts, is called the center of buoyancy d Center of buoyancy is located above the center of gravity of the displaced liquid v e Relative density of liquids can be determined by means of the depth of flotation of hydrometer.

According to the principle of buoyancy a body totally or partially immersed in a fluid will be lifted up by a force equal to a the weight of the body b more than the weight of the body c less than the weight of the body d weight of the fluid displaced by the body e weight of body plus the weight of the fluid displaced hy the body. When a body floating in a liquid, is displaced slightly, it oscillates about a e. Buoyant force is a resultant force acting on a floating body b equal to the volume of liquid displaced c force necessary to keep a body in equilibrium d the resultant force on a body due to the fluid surrounding it e none of the above.

For dynamic similarity, at what velocity should a model be towed through water? A model of a reservior is drained in 4 mts by opening the sluice gate. The model scale is 1: How long should it take to empty the prototype? What model scale has been used? For a floating body to be in stable equilibrium, its metacentre should be a below the center of gravity b below the center of buoyancy c above the center of buoyancy d between e.

For a floating body to be in equilibrium a meta centre should be above e. The two important forces for a floating body are a buoyancy, gravity b buoyancy, pressure c buoyancy, inertial d inertial, gravity e gravity, pressure.

Choose the wrong statement a The center of buoyancy is located at the center of gravity of the displaced liquid b For stability of a submerged body, the center of gravity of body must lie directly below the center of buoyancy c If e.

Center of pressure on an inclined plane is a at the centroid b above the centroid c below the centroid d at metacentre e at center of pressure. An open vessel of water is accelerated up an inclined plane. The free water surface will a be horizontal b make an angle in direction of inclination of inclined plane c make an angle in opposite direction to inclination of inclined plane d any one of above is possible e none of the above.

The line of action of the buoyant force acts through the centroid of the a submerged body b volume of the floating body c volume of the fluid vertically above the body d displaced volume of the fluid e none of the above. Resultant pressure of the liquid in the case of an immersed body acts through a centre of gravity b centre of pressure c metacentre d centre of buoyancy e in between e.

The centre of gravity of the volume of the liquid displaced by an immersed body is called a centre of gravity b centre of pressure c metacentre d centre of buoyancy e centroid. Differential monometer is used to measure a pressure in pipes, channels etc. The pressure in the air space above an oil sp. The pressure at 2. In an immersed body, centre of pressure is a at the centre of gravity b above the centre of gravity c below be centre of gravity d could be above or below e.

The normal stress is same in all directions at a point in a fluid a only when the fluid is frictionless b only when the fluid is incompressible and has zero viscosity c when there is no motion of one fluid layer relative to an adjacent layer d irrespective of the motion of one fluid layer relative to an adjacent layer e in case of an ideal fluid. For measuring flow by a venturimeter, if should be installed in a vertical line b horizontal line c inclined line with flow downward d inclined line with upward flow e in any direction and in any location.

Total pressure on a lmxlm gate immersed vertically at a depth of 2 m below the free water surface will be a kg b kg c kg d kg e kg.

Hot wire anemometer is used to measure a pressure in gases b liquid discharge c pressure in liquids d gas velocities e temperature. Rotameter is a device used to measure a absolute pressure b velocity of fluid c flow d rotation e velocity of air. True one-dimensional flow occurs when a the direction and magnitude of the veiocity at all points are identical b the velocity of successive fluid par-ticles, at any point, is the same at suc-cessive periods of time c the magnitude and direction of the velocity do not change from point to point in the fluid d the fluid particles move in plane or parallel planes and the streamline pat-terns are identical in each plane e velocity, depth, pressure etc.

In the case of steady flow of a fluid, the acceleration of any fluid particle is a constant b variable c zero d zero under limiting conditions e never zero. Non uniform flow occurs when a the direction and magnitude of the velocity at all points are identical b the velocity of successive fluid particles, at any point, is the same at successive periods of time c the magnitude aricf direction of the velocity do not change from point to point in the fluid d the fluid particles move in plane or parallel planes and the streamline pat-terns are identical in each plane e velocity, depth, pressure, etc.

During the opening of a valve in a pipe line, the flow is a steady b unsteady c uniform d laminar e free vortex type. Uniform flow occurs when a the flow is steady b the flow is streamline c size and shape of the cross section in a particular length remain constant d size and cross section change uniformly along length e flow occurs at constant fate. Gradually varied flow is a steady uniform b non-steady non-uniform c non-steady uniform d steady non-uniform e true one-dimensional. Steady flow occurs when a the direction and magnitude of the velocity at all points are identical b the velocity of successive fluid particles, at any point, is the same at successive periods of time c the magnitude and direction of the velocity do not change from point to point in the fluid d the fluid particles move in plane or parallel planes and the streamline pat-terns are identical in each plane e velocity, depth, pressure, etc.

The flow which neglects changes in a transverse direction is known as a one dimensional flow b uniform flow c steady flow d turbulent flow e streamline flow.

The flow in which each liquid particle has a definite path and their paths do not cross each other is called a one dimensional flow b uniform flow c steady flow d turbulent flow e streamline flow. The flow in which conditions do not change with time at any point, is known as a one dimensional flow b uniform flow c steady flow d turbulent flow e streamline flow. The flow in which the velocity vector is identical in magnitude and direction at every point, for any given instant, is known as a one dimensional flow b uniform flow c steady flow d turbulent flow e streamline flow.

The flow in which the particles of a fluid attain such velocities that vary from point to point in magnitude and direction as well as from instant to instant, is known as a one dimensional flow b uniform flow c steady flow d turbulent flow e streamline flow. Flow occurring in a pipeline when a valve is being opened is a steady b unsteady c laminar d vortex e rotational. General energy equation holds for a steady flow b turbulent flow c laminar flow d non-uniform flow e all of the above.

A streamline is defined as the line a parallel to central axis flow b parallel to outer surface of pipe c of equal yelocity in a flow d along which the pressure drop is uniform e which occurs in all flows. Two dimensional flow occurs when a the direction and magnitude of the velocity at all points are identical b the velocity of successive fluid particles, at any point, is the same at successive periods of time c the magnitude and direction of the velocity do not change from point to point in the fluid d the fluid particles move in plane or parallel planes and the streamline pat-terns are identical in each plane e velocity, depth, pressure, etc.

A piece of metal of specific gravity 7 floats in mercury of specific gravity What fraction of its volume is under mercury?

The specific gravity of wood is a 0. In a free vortex motion, the radial component of velocity everywhere is a maximum b minimum c zero d non-zero and finite e unpredictable. In a forced vortex, the velocity of flow everywhere within the fluid is a maximum b minimum c zero d non-zero finite e unpredictable.

The region between the separation streamline and the boundary surface of the solid body is known as a wake b drag c lift d boundary layer e aerofoil section. For hypersonic flow, the Mach number is a unity b greater than unity c greater than 2 d greater than 4 e greater than The upper surface of a weir over which water flows is known is a crest b nappe c sill d weir top e contracta.

Normal depth in open channel flow is the depth of flow corresponding to a steady flow b unsteady flow c laminar flow d uniform flow e critical flow. Uniform flow occurs when a the direction and magnitude of the velocity at all points are identical b the velocity of successive fluid paiticles, at any point, is the same at successive periods of time c the magnitude and direction of the velocity do not change from point to point in the fluid d the fluid particles move in plane or parallel planes and the streamline pat-terns are identical in each pleasure e velocity, depth, pressure, etc.

Pitot tube is used for measurement of a pressure b flow c velocity d dsscharge e viscosity. Hydrometer is used to determine a specific gravity of liquids b specific gravity of solids c specific gravity of gases d relative humidity e density. The equation of continuity holds good when the flow a is steady b is one dimensional c velocity is uniform at all the cross sections d all of the above e none of the above.

Mach number is significant in a supersonics, as with projectiles and jet propulsion b full immersion or completely enclosed flow, as with pipes, aircraft wings, nozzles etc.

Multiple Choice Questions for Physics Semiconductors. Multiple Choice Questions for Physics Gravitation. Multiple Choice Questions for Physics Oscillations. Multiple Choice Questions for Physics Thermodynamics. Notes Free revision notes, brief chapter explanations, chapter summary and mind maps for all important and difficult topics of NEET Physics Fluid Mechanics as per Read More. An open cubical tank of 2 m side is filled with water. A right circular cylinder open at the top is filled with liquid and rotated about its vertical axis at such a speed that half the liquid spills out, then the pressure intensity at the center of bottom is a zero b one-fourth its value when cylinder was full c one-half its value when cylinder was full d cannot be predicted from the given data Answer: a.

The horizontal component of force on a curved surface is equal to the a product of pressure intensity at its centroid and area b force on a vertical projection of the curved surface c weight of liquid vertically above the curved surface d force on the horizontal projection of the curved surface Answer: b. A closed tank containing water is moving in a horizontal direction along a straight line at a constant speed.

The tank also contains a steel ball and a bubble of air. If the tank is decelerated horizontally, then i the ball will move to the front ii the bubble will move to the front iii the ball will move to the rear iv the bubble will move to the rear Find out which of the above statements are correct?

The eddy viscosity for turbulent flow is a a function of temperature only b a physical property of the fluid. Flow at constant rate through a tapering pipe is i steady flow ii uniform flow iii unsteady flow iv non-uniform flow The correct answer is a i and ii b i and iv c ii and iii d ii and iv Answer: b. The velocity near the airfoil, where the stream lines are 1. Answer: c. Least possible value of correction factor for i kinetic energy is zero ii kinetic energy is 1 iii momentum is zero iv momentum is 1 The correct statements are a i and iii b ii and iii c i and iv d ii and iv Answer: d.

Which of the following velocity potentials satisfies continuity equation? The motion of air mass in a tornado is a a free vortex motion b forced vortex motion c free vortex at center and forced vortex outside d forced vortex at center and free vortex outside Answer: d.

In a forced vortex motion, the velocity of flow is a directly proportional to its radial distance from axis of rotation b inversely proportional to its radial distance from the axis of rotation c inversely proportional to the square of its radial distance from the axis of rotation d directly proportional to the square of its radial distance from the axis of rotation Answer: a.

Stream lines and path lines always coincide in case of a steady flow b laminar flow c uniform flow d turbulent flow Answer: a. Equation of continuity is based on the principle of conservation of a mass b energy c momentum d none of the above Answer: a.

In steady flow of a fluid, the total accele ration of any fluid particle a can be zero b is never zero c is always zero d is independent of coordinates Answer: a.

The pitot tube is used to measure a velocity at stagnation point b stagnation pressure c static pressure d dynamic pressure Answer: b. Hot wire anemometer is used to measure a discharge b velocity of gas c pressure intensity of gas d pressure intensity of liquid Answer: b. The theoretical value of coefficient of contraction of a sharp edged orifice is a 0. Which of the following is used to measure the discharge? Select the incorrect statement. Size of a venturimeter is specified by a pipe diameter b throat diameter c angle of diverging section d both pipe diameter as well as throat diameter Answer: a.

Which of the following is an incorrect statement? Answer: d. Coefficient of velocity of venturimeter a is independent of Reynolds number b decreases with higher Reynolds number c is equal to the coefficient of discharge of venturimeter d none of the above Answer: c. The pressure at the summit of a syphon is a equal to atmospheric b less than atmospheric c more than atmospheric d none of the above Answer: b.

Ay between two stream lines represents a velocity b discharge c head d pressure Answer: b. Coefficient of discharge for a totally submerged orifice as compared to that for an orifice discharging free is a slightly less b slightly more c nearly half d equal Answer: a. The major loss of energy in long pipes is due to a sudden enlargement b sudden contraction c gradual contraction or enlargement d friction Answer: d.

Coefficient of contraction for an external cylindrical mouthpiece is a 1. Which of the following has highest coefficient of discharge? Which of the following statements is correct? The shear stress distribution for a fluid flowing in between the parallel plates, both at rest, is a constant over the cross section b parabolic distribution across the section c zero at the mid plane and varies linearly with distance from mid plane d zero at plates and increases linearly to midpoint Answer: c.

Stanton diagram is a a log-log plot of friction factor against Reynolds number b log-log plot of relative roughness against Reynolds number c semi-log plot of friction factor against Reynolds number d semi-log plot of friction factor against relative roughness Answer: a.

If the velocity is zero over half of the cross-sectional area and is uniform over the remaining half, then the momentum correction factor is. Posted by engineering raju at Email This BlogThis! No comments:. Newer Post Older Post Home.