Description : Momentum transfer in laminar flow of fluids results due to the (A) Viscosity (B) Density (C) Velocity gradient (D) None of these
Last Answer : (C) Velocity gradient
Description : For laminar flow of Newtonian fluids through a circular pipe, for a given pressure drop and length & diameter of pipe, the velocity of fluid is proportional to (where, μ = fluid viscosity ) (A) μ (B) 1/μ (C) √μ (D) 1/√μ
Last Answer : (B) 1/μ
Description : Two fluids are flowing through two similar pipes of the same diameter. The Reynold's number is same. For the same flow rate if the viscosity of a fluid is reduced to half the value of the ... (A) Increase (B) Decrease (C) Remain unchanged (D) Data insufficient to predict relative pressure drop
Last Answer : (B) Decrease
Description : In a parallel flow heat exchanger, if the outlet temperature of hot and cold fluids are the same, then the log mean temperature difference (LMTD) is (A) Minimum (B) Maximum (C) Zero (D) Infinity
Last Answer : (C) Zero
Description : Property of a fluid by which molecules of different kinds of fluids are attracted to each other is called (A) Adhesion (B) Cohesion (C) Viscosity (D) Compressibility
Last Answer : Answer: Option A
Description : Many common household fluids, such as margarine, undergo a decrease in viscosity when subjected to a shearing force. What is this property called?
Last Answer : ANSWER: THIXOTROPIC (pron: thik-sa-trop-ick)
Description : Plate towers are preferred to packed towers, when large temperature changes are involved, because of the reason that the (A) Packing may be crushed due to thermal expansion/contraction of the ... C) Viscosity variation of the fluids may cause channelling/flooding (D) None of these
Last Answer : (A) Packing may be crushed due to thermal expansion/contraction of the components of the equipments
Description : With increase in the shear rate, the apparent viscosity of pseudo-plastic fluids (A) Increases (B) Decreases (C) Remain same (D) May increase or decrease; depends on the magnitude of shear rate
Last Answer : (B) Decreases
Description : Power required for mixing Newtonian fluids is a function of the (A) Speed of impeller, diameter of impeller & viscosity (B) Density & viscosity of fluid only (C) Density of fluid, viscosity of fluid & impeller dia only (D) None of these
Last Answer : (D) None of these
Description : Poise is the unit of (A) Surface tension (B) Capillarity (C) Viscosity (D) Shear stress in fluids
Last Answer : Answer: Option C
Description : Which one of the following statements is correct ? (a) Dynamic viscosity is the property of a fluid which is not in motion (b) Surface energy is a fluid property giving rise to the phenomenon ... results from the action of very high pressure (d) Real fluids have lower viscosity than ideal fluids
Last Answer : (d) Real fluids have lower viscosity than ideal fluids
Description : Which of the following must be followed by the flow of a fluid (real or ideal)? (I) Newton's law of viscosity. (II) Newton's second law of motion. (III) The continuity equation. (IV) Velocity of boundary layer must be zero relative to ... . (A) I, II, III (B) II, III, V (C) I, II, V (D) II, IV, V
Last Answer : (B) II, III, V
Description : Consider the following statements in respect of steady laminar flow through a circular pipe: 1. Shear stress is zero on the central axis of the pipe 2. Discharge varies directly with the viscosity of the fluid 3. Velocity is maximum at the ... 2 , 3 & 4 (b) 1 & 3 only (c) 2 & 4 only (d)3 & 4 only
Last Answer : (b) 1 & 3 only
Description : Pick out the correct statement pertaining to transition/ entrance length in fluid flow. (A) The length of entrance region of pipe, in which full development of fluid flow takes place such that velocity profile does not change ... pipe of diameter 'd' is equal to 50 D (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : The property to flow is unique to fluids. Which one of the following statements is correct ? -Maths 9th
Last Answer : NEED ANSWER
Last Answer : (c) Gases and liquids behave like fluids. Both gases and liquids tend to flow due to less force of attraction between their particles. Also, they require vessel to keep them. Solids do not flow.
Description : What describes rock through which fluids can flow easily?
Last Answer : Need answer
Description : Solid particles separation based on the difference in their flow velocities through fluids is termed as the (A) Clarification (B) Classification (C) Elutriation (D) Sedimentation
Last Answer : (B) Classification
Description : When both the fluids flow concurrently in an absorber, the slope of the operating line is (A) -ve (B) +ve (C) 1 (D) -1
Last Answer : (A) -ve
Description : A 2-4 heat exchanger involves (A) Only counter-flow of fluids (B) Only parallel-flow of fluids (C) Both counter and parallel-flow of the fluids (D) Smaller pressure drop compared to 1-2 exchanger
Last Answer : (C) Both counter and parallel-flow of the fluids
Description : Pick out the wrong statement. (A) The controlling resistance in case of heating of air by condensing steam is in the air film (B) The log mean temperature difference (LMTD) for ... a pure fluid at a given pressure from liquid to vapor or vice-versa occurs at saturation temperature
Last Answer : (C) In case of a 1 - 2 shell and tube heat exchanger, the LMTD correction factor value increases sharply, when a temperature cross occurs
Description : LMTD for evaporators & condensers for a given terminal parameters & set of conditions for counter-flow is equal to that for parallel flow. In such heat exchangers, with one of the fluids condensing or evaporating, the surface ... Parallel (B) Mixed (C) Counter flow (D) Same in either 'a', b' or 'c'
Last Answer : (D) Same in either 'a', b' or 'c'
Description : Dittus-Boelter equation used for the determination of heat transfer coefficient is valid (A) For fluids in laminar flow (B) For fluids in turbulent flow (C) When Grashoff number is very important (D) For liquid metals
Last Answer : (B) For fluids in turbulent flow
Description : Which one of the following statements is incorrect? (a) The principle of countercurrent flow facilitates efficient respiration in gills of fishes. (b) The residual air in lungs slightly decreases the ... in birds. (d) In insects, circulating body fluids serve to distribute oxygen to tissues.
Last Answer : (b) The residual air in lungs slightly decreases the efficiency of respiration in mammals.
Description : The Stoke's stream function applies to the (A) Irrotational flow only (B) Ideal/non i viscous fluids only (C) Cases of axial symmetry (D) None of these
Last Answer : (C) Cases of axial symmetry
Description : For flow of fluids through packed bed, the superficial velocity is (A) Less than the average velocity through channels (B) More than the average velocity through channels (C) Dependent on the pressure drop across the bed (D) Same as the average velocity through channels
Last Answer : (A) Less than the average velocity through channels
Description : Pick out the wrong statement. (A) The shear stress at the pipe (dia = D, length = L) wall in case of laminar flow of Newtonian fluids is (D/4L). ∆p (B) In the equation, T. gc = k. ... to motion (D) With increase in the Mach number >0.6, the drag co-efficient decreases in case of compressible fluids
Last Answer : (D) With increase in the Mach number >0.6, the drag co-efficient decreases in case of compressible fluids
Description : The energy equation, E + (p/ρ) + (V 2 /2g) + gZ = constant (E = internal energy/mass), is applicable to (A) Perfect gases only (B) Isothermal flow of gases (C) Adiabatic unsteady flow of gases (D) All compressible fluids
Last Answer : (D) All compressible fluids
Description : A mixed flow centrifugal pump (A) Employs such an impeller, through which the flow is a combination of radial & axial flow (B) Mixes the two fluids before pumping them (C) Pumps the two fluids separately and then mixes them (D) Employs impellers in both the radial & axial directions
Last Answer : (A) Employs such an impeller, through which the flow is a combination of radial & axial flow
Description : Potential flow is the flow of (A) Compressible fluids with shear (B) Compressible fluids with no shear (C) Incompressible fluids with shear (D) Incompressible fluids with no shear
Last Answer : (D) Incompressible fluids with no shear
Description : Boundary layer exists in flow (A) Of real fluids (B) Over flat surfaces only (C) In pipes only (D) Of ideal fluids only
Last Answer : (A) Of real fluids
Description : The effect of solid boundary on the fluid flow is confined to the boundary layer, except for fluids (A) Having high viscosities (B) Moving at low velocities (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) & (B)
Description : In a/an __________, the flow rate of fluids is obtained by measuring the difference between the impact and the static pressure. (A) Rotameter (B) Pitot tube (C) Venturimeter (D) Flow nozzle
Last Answer : (B) Pitot tube
Description : Which of the following facilitates close control of flow of fluids? (A) Gate valve (B) Globe valve (C) Butterfly valve (D) Check valve
Last Answer : (B) Globe valve
Description : Venturimeter is used to measure the flow rate of fluids in pipes, when the pipe is in __________ position. (A) Horizontal (B) Vertical (C) Inclined (D) Any
Last Answer : (D) Any
Description : Parallel straight line pattern of temperature distribution for both hot and cold fluids is observed in case of heat exchanger of the type (A) Parallel flow with equal heat capacities (B) Counter ... (C) Counter flow with unequal heat capacities (D) Parallel flow with unequal heat capacities
Last Answer : (B) Counter flow with equal heat capacities
Description : Froude number is significant in (A) Supersonics, as with projectile and jet propulsion (B) Full immersion or completely enclosed flow, as with pipes, aircraft wings, nozzles etc. (C) Simultaneous motion ... gravity forces, and wave making effect, as with ship's hulls (D) All of the above
Description : The continuity equation is connected with (A) Open channel/pipe flow (B) Compressibility of fluids (C) Conservation of mass (D) Steady/unsteady flow
Description : Reynolds number is significant in (A) Supersonics, as with projectile and jet propulsion (B) Full immersion or completely enclosed flow, as with pipes, aircraft wings, nozzles etc. (C) Simultaneous motion ... gravity forces, and wave making effect, as with ship's hulls (D) All of the above
Last Answer : Answer: Option B
Description : 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. (C) Simultaneous motion through ... gravity force, and wave making effects, as with ship's hulls (D) All of the above
Description : Recuperated will be more efficient if the flow path of hot and cold fluids is in: a) Co-current mode b) Counter current mode c) Cross current mode d) Cone of the above
Last Answer : Counter current mode
Description : A perfect gas (A) Does not satisfy PV = nRT (B) Is incompressible and has zero viscosity (C) Has constant specific heat (D) Can’t develop shear stresses
Last Answer : (C) Has constant specific heat
Description : The normal stress is the same in all directions at a point in a fluid, only when the fluid (A) Is at rest & has zero viscosity (B) Is frictionless (C) Fluid layer has no motion relative to an adjacent layer of fluid (D) is incompressible & frictionless
Last Answer : (D) is incompressible & frictionless
Description : 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 ... to an adjacent layer (D) Irrespective of the motion of one fluid layer relative to an adjacent layer
Description : The normal stress in a fluid will be constant in all directions at a point only if (A) It is incompressible (B) It has uniform viscosity (C) It has zero viscosity (D) It is at rest
Last Answer : Answer: Option D
Description : A perfect gas (A) Has constant viscosity (B) Has zero viscosity (C) Is in compressible (D) None of the above
Description : A flow in which the viscosity of fluid is dominating over the inertia force is called (A) Steady flow (B) Unsteady flow (C) Laminar flow (D) Turbulent flow
Description : A flow in which __________ force is dominating over the viscosity is called turbulent flow. (A) Elastic (B) Surface tension (C) Viscous (D) Inertia
Description : The process of one substance mixing with another because of molecular motion is called _________. a. diffusion b. viscosity c. streamline flow d. solution
Last Answer : diffusion
Description : A fountain pen works on the principle of (1) Flow of liquids from higher to lower potential (2) Capillary action (3) Bernoulli's principle (4) Viscosity of liquids
Last Answer : (2) Capillary action Explanation: A fountain pen is a nib pen that, unlike its predecessor the dip pen, contains an internal reservoir of water-based liquid ink. The pen draws ink from the ... to flow in narrow spaces without the assistance of, and in opposition to external forces like gravity.