Description : The co-efficient of drag and lift for an incompressible fluid depends on the (A) Reynolds number (B) Froude number (C) Mach number (D) All (A), (B) and (C)
Last Answer : (A) Reynolds numbe
Description : Which of the following is not a dimension-less parameter? (A) Pressure-co-efficient (B) Froude number (C) Kinematic viscosity (D) Weber number
Last Answer : (C) Kinematic viscosity
Description : In Newton's law range, the drag co-efficient for the motion of spherical particle in a stationary fluid is (A) 0.44 (B) 0.044 (C) 4.4 (D) 44
Last Answer : (A) 0.44
Description : __________ number determines whether the fluid flow in an open channel is supercritical, critical or sub-critical. (A) Mach (B) Reynolds (C) Froude (D) Weber
Last Answer : (C) Froude
Description : Which of the following is directly concerned with Psychrometry? (A) Lewis relationship (B) Galileo number (C) Weber number (D) Dean number
Last Answer : (A) Lewis relationship
Description : Dean number is concerned with the (A) Fluid-particle interaction (B) Fluid flow through helical pipes (C) Power consumption in agitated vessels (D) Psychrometry
Last Answer : (B) Fluid flow through helical pipes
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 : Drag co-efficient for motion of spherical particles in a stationary fluid in the stoke's law range is (A) 24/NRe,P (B) 16/NRe,P (C) 64/NRe,P (D) 48/NRe,P
Last Answer : (A) 24/NRe,P
Description : The ratio of inertial forces to gravity forces is called the __________ number. (A) Mach (B) Froude (C) Euler (D) Weber
Last Answer : (B) Froude
Description : Ratio of pressure and inertia force gives __________ number. (A) Weber (B) Mach (C) Euler (D) Froude
Last Answer : (C) Euler
Description : Ratio of inertial forces to surface tension forces is called the __________ number. (A) Euler (B) Froude (C) Mach (D) Weber
Last Answer : (D) Weber
Description : The ratio of inertial forces to viscous forces is called the __________ number. (A) Weber (B) Mach (C) Froude (D) Reynold
Last Answer : (D) Reynold
Description : Which of the following is not dimension-less? (A) Froude number (B) Kinematic viscosity (C) Pressure co-efficient (D) None of these
Last Answer : (B) Kinematic viscosity
Description : Froude number is the ratio of (A) Shear stress to gravitational stress (B) Drag stress to shear stress (C) Inertial stress to shear stress (D) Inertial stress to gravitational stress
Last Answer : (D) Inertial stress to gravitational stress
Description : __________ forces act on a particle moving through a stationary fluid (A) Gravity (B) Drag (C) Buoyant (D) All (A), (B), & (C)
Last Answer : (D) All (A), (B), & (C)
Description : For motion of spherical particles in a stationary fluid, the drag coefficient in hindered settling compared to that in free settling is (A) More (B) Less (C) Equal (D) More or less, depending on the type of particle
Last Answer : (A) More
Description : Forces acting on a particle settling in fluid are __________ forces. (A) Gravitational & buoyant (B) Centrifugal & drag (C) Gravitational or centrifugal buoyant drag (D) External, drag & viscous
Last Answer : (C) Gravitational or centrifugal buoyant drag
Description : Which is not concerned directly with mass transfer? (A) Schmidt number (B) Sherwood number (C) Lewis relationship (D) Froude number
Last Answer : (D) Froude number
Description : Which of the following is concerned with both heat and mass transfer? (A) Lewis relationship (B) Nusselt number (C) Kutateladze number (D) Froude number
Description : For a sphere falling in the constant drag co-efficient regime, its terminal velocity depends on its diameter (D) as (A) d (B) √d (C) d 2 (D) 1/d
Last Answer : (C) d
Description : The drag co-efficient for a bacterium moving in water at 1 mm/s, will be of the following order of magnitude (assume size of the bacterium to be 1 micron and kinematic viscosity of water to be 10 -6m2 /s). (A) 24000 (B) 24 (C) 0.24(D) 0.44
Last Answer : (D) 0.44
Description : Drag co-efficient for flow past immersed body is the ratio of __________ to the product of velocity head and density. (A) Shear stress (B) Shear force (C) Average drag per unit projected area (D) None of these
Last Answer : (C) Average drag per unit projected area
Description : Weber number is significant and is concerned with the (A) Solid-liquid mixing (B) Liquid-liquid mixing (C) Dispersion of liquid in liquid (D) Suspension of solid in liquid
Last Answer : (C) Dispersion of liquid in liquid
Description : Drag co-efficient in hindered settling is __________ that in free settling. (A) Less than (B) Equal to (C) Not necessarily greater than (D) Always greater than
Last Answer : (D) Always greater than
Description : Which of the following denotes the effect of compressibility in fluid flow? (A) Weber number (B) Mach number (C) Euler number (D) Reynolds number
Last Answer : (B) Mach numbe
Description : . Which of the following relationships between co-efficient of friction (μ) between rock & roll and a (half of the angle of nip) of the particle to be crushed is correct? (A) μ > tan α (B) μ ≥ tan α (C) μ > tan 2α (D) μ ≤ tan α
Last Answer : (B) μ ≥ tan α
Description : A spherical particle is falling slow in a viscous liquid such that Reynolds number is less than 1. Which statement is correct for this situation? (A) Inertial and drag forces are important (B) Drag ... forces are important (C) Drag force and gravitational forces are important (D) None of the above
Last Answer : (B) Drag, gravitational and buoyancy forces are important
Description : For a particle settling in water at its terminal settling velocity, which of the following is true? (A) Buoyancy = weight + drag (B) Weight = buoyancy + drag (C) Drag = buoyancy + weight (D) Drag = weight
Last Answer : (B) Weight = buoyancy + drag
Description : Pick out the wrong statement. (A) Superheated steam is preferably not used for process heating because of its low heat transfer film co-efficient (B) In a shell and tube heat exchanger ... surface heat exchangers, when the direction of fluid flow is parallel to the axis of the tube
Last Answer : (C) S.I. unit of fouling factor is Watt/m2 .°K
Description : Convective heat transfer co-efficient in case of fluid flowing in tubes is not affected by the tube length/diameter ratio, if the flow is in the __________ zone. (A) Laminar (B) Transition (C) Both 'a' & 'b' (D) Highly turbulent
Last Answer : (D) Highly turbulent
Description : Heat transfer co-efficient (h) for a fluid flowing inside a clean pipe is given by h = 0.023 (K/D) (DVρ/µ) 0.8 (CP .µ/k) 0.4 . This is valid for the value of NRe equal to (A) < 2100 (B) 2100-4000 (C) > 4000 (D) > 10000
Last Answer : (D) > 10000
Description : In an extended surface heat exchanger, fluid having lower co-efficient (A) Flows through the tube (B) Flows outside the tubes (C) Can flow either inside or outside the tubes (D) Should not be used as it gives very high pressure drop
Last Answer : (B) Flows outside the tubes
Description : Out of the following four assumptions used in the derivation of theequation for LMTD [LMTD = (∆t1 - ∆t2 )/ln(∆t1 /∆t2 )], which one is subject to the largest deviation in practice ? (A) Constant ... (B) Constant rate of fluid flow (C) Constant specific heat (D) No partial phase change in the system
Last Answer : (B) Constant rate of fluid flow
Description : For a laminar flow of fluid in a circular tube, 'h1 ' is the convective heat transfer co-efficient at velocity 'V1 '. If the velocity is reduced by half and assuming the fluid properties are constant, the new convective heat transfer co-efficient is (A) 1.26 h1 (B) 0.794 h1 (C) 0.574 h1 (D) 1.741 h1
Last Answer : (B) 0.794 h1
Description : The fluid jet discharging from a 2" diameter orifice has a diameter of 1.75" at its vena-contracta. The co-efficient of contraction is (A) 1.3 (B) 0.766 (C) 0.87 (D) None of these
Last Answer : (B) 0.766
Description : What is the co-efficient of contraction, if a fluid jet discharging from a 50 mm diameter orifice has a 40 mm diameter at its vena-contracta? (A) 0.64 (B) 1.65 (C) 0.32 (D) 0.94
Last Answer : (A) 0.64
Description : The contraction co-efficient for Borda's mouthpiece (for frictionless fluid) is (A) 0.1 (B) 0.5 (C) 0.94 (D) 1
Last Answer : (B) 0.5
Description : A particle moves along a rough plane inclined at 30? to the horizontal. The co-efficient of friction between the particle and the plane is 0.1. Its initial velocity is 15 m/sec. The ratio of the velocity of the particle when it move ... be in the regions a.8 ? 10 b.5 ? 7 c.2 ? 3 d.4 ? 6 e.10 ? 13
Last Answer : b. 5 ? 7
Description : . In case of turbulent flow of fluid through a circular pipe, the (A) Mean flow velocity is about 0.5 times the maximum velocity (B) Velocity profile becomes flatter and flatter with ... , shear stresses, random orientation of fluid particles and slope of velocity profile at the wall are more
Last Answer : (D) Skin friction drag, shear stresses, random orientation of fluid particles and slope of velocity profile at the wall are more
Description : Deformation drag, which is caused by widespread deformation of fluid around the immersed body (A) Occurs when NRe is very small (B) Is primarily a friction drag (C) Is independent of body length (D) Depends mainly on cross-sectional shape
Last Answer : (A) Occurs when NRe is very small
Description : The ratio of the wall drag to the form drag in the Stoke's law range (for motion of spherical particles in a stationary fluid) is (A) 0.5 (B) 1 (C) 2 (D) 0.33
Last Answer : (C) 2
Description : Drag force acting on a body does not depend upon the (A) Density of the fluid (B) Density of the body (C) Velocity of the body (D) Projected area of the body
Last Answer : (B) Density of the body
Description : In fluid flow, the boundary layer separation cannot occur (A) In case of boundaries experiencing form drag (B) At points of abrupt changes in the flow directions (C) In laminar flow (D) None of theseIn ... B) At points of abrupt changes in the flow directions (C) In laminar flow (D) None of these
Last Answer : (D) None of these
Description : Pick out the wrong statement. (A) The form drag is dependent upon the occurrence of a wake (B) The shear stress at any given cross-section of a pipe for steady flow (either laminar or turbulent ... of viscosity (D) Existence of the boundary layer in fluid flow is because of viscosity of the fluid
Last Answer : (C) An ideal fluid is the one, which has negligible surface tension and obeys the Newton's law of viscosity
Description : Drag is defined as the force exerted by the (A) Fluid on the solid in a direction opposite to flow (B) Fluid on the solid in the direction of flow (C) Solid on the fluid (D) None of these
Last Answer : (B) Fluid on the solid in the direction of flow
Description : The important dimensional group involved in the power requirement calculation in mixing operation is the __________ number. (A) Reynold's (B) Froude (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) & (B)
Description : During agitation of liquids, the (A) Froude number is independent for the curves between power number and Reynolds number in baffled system (B) Power number becomes independent of impellers Reynolds number at high Reynolds number, ... , the centre vortex) on the power number (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Froude number is not a factor (A) For Reynolds number greater than 300 (B) When there is no vortex formation (C) For unbaffled tank (D) None of these
Last Answer : (B) When there is no vortex formation
Description : The ratio of pressure forces to inertial forces is called the __________ number. (A) Froude (B) Euler (C) Reynold (D) Mach
Last Answer : (B) Euler
Description : Do particles record every interaction they make with every other particle they encounter?
Last Answer : Yes, but they record' their interactions with everything they encounter. Each interaction imparts some impulse but the echo of that dissipates with time. Particles are interacting with other particles ... the particular event you were attempting to record from the events before or after it.