The flow in a pipe is neither laminar nor turbulent when Reynold number is (A) Less than 2000 (B) Between 2000 and 2800 (C) More than 2800 (D) None of these

The flow in a pipe is neither laminar nor turbulent when Reynold number is
(A) Less than 2000
(B) Between 2000 and 2800
(C) More than 2800
(D) None of these
by

1 Answer

Answer :

Answer: Option B
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Related questions

The flow in a pipe is turbulent when Reynold number is (A) Less than 2000 (B) Between 2000 and 2800 (C) More than 2800 (D) None of these

Description : The flow in a pipe is turbulent when Reynold number is (A) Less than 2000 (B) Between 2000 and 2800 (C) More than 2800 (D) None of these

Last Answer : Answer: Option C

05. The flow in a pipe is laminar, when Reynold number is less than 2000. A) True B) False

Description : 05. The flow in a pipe is laminar, when Reynold number is less than 2000. A) True B) False

Last Answer : A

A large Reynold number is indication of (A) Smooth and streamline flow (B) Laminar flow (C) Steady flow (D) Highly turbulent flow

Description : A large Reynold number is indication of (A) Smooth and streamline flow (B) Laminar flow (C) Steady flow (D) Highly turbulent flow

Last Answer : Answer: Option D

Aerodynamic noise resulting from turbulent gas flow is the most prevalent source of valve noise in fluid flow control. It is caused due to (A) Reynold stresses (B) Shear forces (C) Both (A) & (B) (D) Neither (A) nor (B)

Description : Aerodynamic noise resulting from turbulent gas flow is the most prevalent source of valve noise in fluid flow control. It is caused due to (A) Reynold stresses (B) Shear forces (C) Both (A) & (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) & (B)

Pick out the correct statement. (A) A forced vortex occurs when fluid rotates as a solid about an axis (B) In laminar flow, Newton's law of viscosity does not apply (C) A free vortex occurs, when fluid rotates as a solid (D) In turbulent flow, there are neither cross-currents nor eddies

Description : Pick out the correct statement. (A) A forced vortex occurs when fluid rotates as a solid about an axis (B) In laminar flow, Newton's law of viscosity does not apply (C) A free vortex occurs, when fluid rotates as a solid (D) In turbulent flow, there are neither cross-currents nor eddies

Last Answer : (A) A forced vortex occurs when fluid rotates as a solid about an axis

Fanning friction factor for laminar flow of fluid in a circular pipe is (A) Not a function of the roughness of pipe wall (B) Inversely proportional to Reynolds number (C) Both (A) & (B) (D) Neither (A) nor (B)

Description : Fanning friction factor for laminar flow of fluid in a circular pipe is (A) Not a function of the roughness of pipe wall (B) Inversely proportional to Reynolds number (C) Both (A) & (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) & (B)

The velocity corresponding to Reynold number of 2800, is called (A) Sub-sonic velocity (B) Super-sonic velocity (C) Lower critical velocity (D) Higher critical velocity

Description : The velocity corresponding to Reynold number of 2800, is called (A) Sub-sonic velocity (B) Super-sonic velocity (C) Lower critical velocity (D) Higher critical velocity

Last Answer : Answer: Option D

In turbulent flow, a rough pipe has the same friction factor as a smooth pipe (A) In the zone of complete turbulence (B) When the roughness projections are much smaller than the thickness of the laminar film (C) Everywhere in the transition zone (D) When the friction factor is independent of the Reynold's number

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Last Answer : (B) When the roughness projections are much smaller than the thickness of the laminar film

When the pipe Reynold's number is 6000, the flow is generally (A) Viscous(B) Laminar(C) Turbulent(D) Transition

Description : When the pipe Reynold's number is 6000, the flow is generally (A) Viscous (B) Laminar (C) Turbulent (D) Transition

Last Answer : (C) Turbulent

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) varies linearly as the radial distance (C) An ideal fluid is the one, which has negligible surface tension and obeys the Newton's law of viscosity (D) Existence of the boundary layer in fluid flow is because of viscosity of the fluid

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Last Answer : (C) An ideal fluid is the one, which has negligible surface tension and obeys the Newton's law of viscosity

Transition from laminar flow to turbulent flow in fluid flow through a pipe does not depend upon the (A) Length of the pipe (B) Diameter of the pipe (C) Density of the fluid (D) Velocity of the fluid

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Last Answer : (A) Length of the pipe

The loss of head due to friction in a pipe of uniform diameter in which a viscous flow is taking place, is (where RN = Reynold number) (A) 1/RN (B) 4/RN (C) 16/RN (D) 64/RN

Description : The loss of head due to friction in a pipe of uniform diameter in which a viscous flow is taking place, is (where RN = Reynold number) (A) 1/RN (B) 4/RN (C) 16/RN (D) 64/RN

Last Answer : Answer: Option C

For pipes, laminar flow occurs when Reynolds number is (A) Less than 2000 (B) Between 2000 and 4000 (C) More than 4000 (D) Less than 4000

Description : For pipes, laminar flow occurs when Reynolds number is (A) Less than 2000 (B) Between 2000 and 4000 (C) More than 4000 (D) Less than 4000

Last Answer : Answer: Option A

For pipes, turbulent flow occurs when Reynolds number is(A) Less than 2000 (B) Between 2000 and 4000 (C) More than 4000 (D) Less than 4000

Description : For pipes, turbulent flow occurs when Reynolds number is (A) Less than 2000 (B) Between 2000 and 4000 (C) More than 4000 (D) Less than 4000

Last Answer : Answer: Option C

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 the viscosity of fluid is dominating over the inertia force is called (A) Steady flow (B) Unsteady flow (C) Laminar flow (D) Turbulent flow

Last Answer : Answer: Option C

General energy equation holds for (A) Steady flow (B) Turbulent flow (C) Laminar flow (D) Non-uniform flow

Description : General energy equation holds for (A) Steady flow (B) Turbulent flow (C) Laminar flow (D) Non-uniform flow

Last Answer : Answer: Option D

The velocity at which the flow changes from laminar flow to turbulent flow is called (A) Critical velocity (B) Velocity of approach (C) Sub-sonic velocity (D) Super-sonic velocity

Description : The velocity at which the flow changes from laminar flow to turbulent flow is called (A) Critical velocity (B) Velocity of approach (C) Sub-sonic velocity (D) Super-sonic velocity

Last Answer : Answer: Option A

Isothermal turbulent flow of a fluid results in decrease of its pressure, which depends on the (A) Wall roughness (B) Reynolds number (C) Both (A) & (B) (D) Neither (A) nor (B)

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Last Answer : (C) Both (A) & (B)

In case of hydraulically smooth pipe, the resistance to flow depends only on the Reynolds number, whereas for a hydraulically rough pipe, the resistance to flow is governed by the relative roughness. Two pipes are said to have the same hydraulic roughness, when they have equal values of (A) Relative roughness (B) Absolute roughness (C) Friction co-efficient for flows at equal Reynold number (D) All (A), (B) & (C)

Description : In case of hydraulically smooth pipe, the resistance to flow depends only on the Reynolds number, whereas for a hydraulically rough pipe, the resistance to flow is governed by the relative roughness. Two pipes are said ... co-efficient for flows at equal Reynold number (D) All (A), (B) & (C)

Last Answer : (C) Friction co-efficient for flows at equal Reynold number

In turbulent flow, the (A) Fluid particles move in an orderly manner (B) Momentum transfer is on molecular scale only (C) Shear stress is caused more effectively by cohesion than momentum transfer (D) Shear stresses are generally larger than in a similar laminar flow

Description : In turbulent flow, the (A) Fluid particles move in an orderly manner (B) Momentum transfer is on molecular scale only (C) Shear stress is caused more effectively by cohesion than momentum transfer (D) Shear stresses are generally larger than in a similar laminar flow

Last Answer : (D) Shear stresses are generally larger than in a similar laminar flow

The Graetz number is concerned with the (A) Mass transfer between a gas and a liquid (B) Absorption with chemical reaction (C) Heat transfer in turbulent flow (D) Heat transfer in laminar flow

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Last Answer : (D) Heat transfer in laminar flow

Dittus-Boelter equation used for the determination of heat transfer co￾efficient 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

Description : Dittus-Boelter equation used for the determination of heat transfer co￾efficient 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

Critical value of the __________ number governs the transition from laminar to turbulent flow in free convection heat transfer. (A) Grashoff (B) Reynolds (C) Both 'a' & 'b' (D) Prandtl & Grashoff

Description : Critical value of the __________ number governs the transition from laminar to turbulent flow in free convection heat transfer. (A) Grashoff (B) Reynolds (C) Both 'a' & 'b' (D) Prandtl & Grashoff

Last Answer : (D) Prandtl & Grashoff

Nusselt number is related to the Reynolds number (Re) in turbulent & laminar flow respectively as (A) Re0.5, Re0.8 (B) Re0.8, Re-0.5 (C) Re0.8, Re0.5 (D) Re-0.8, Re0.5

Description : Nusselt number is related to the Reynolds number (Re) in turbulent & laminar flow respectively as (A) Re0.5, Re0.8 (B) Re0.8, Re-0.5 (C) Re0.8, Re0.5 (D) Re-0.8, Re0.5

Last Answer : (C) Re0.8, Re0.5

Nusselt number is related to Grashoff number (Gr) in turbulent & laminar flow respectively, in respect of free convection over a vertical flat plate as (A) Gr0.25, Gr (B) Gr0.25, Gr0.33 (C) Gr, Gr0.25 (D) Gr0.33, Gr0.25

Description : Nusselt number is related to Grashoff number (Gr) in turbulent & laminar flow respectively, in respect of free convection over a vertical flat plate as (A) Gr0.25, Gr (B) Gr0.25, Gr0.33 (C) Gr, Gr0.25 (D) Gr0.33, Gr0.25

Last Answer : Option A

The velocity corresponding to Reynold number of 2000 is called (A) Sub-sonic velocity (B) Super-sonic velocity (C) Lower critical velocity (D) Higher critical velocity

Description : The velocity corresponding to Reynold number of 2000 is called (A) Sub-sonic velocity (B) Super-sonic velocity (C) Lower critical velocity (D) Higher critical velocity

Last Answer : Answer: Option C

In case of a plate and frame filter press, filtrate flow through the cake follows __________ flow. (A) Plug (B) Turbulent (C) Laminar (D) None of these

Description : In case of a plate and frame filter press, filtrate flow through the cake follows __________ flow. (A) Plug (B) Turbulent (C) Laminar (D) None of these

Last Answer : (C) Laminar

A straight line is obtained on plotting reciprocal of filtration rate vs. the volume of filtrate for __________ flow of filtrate. (A) Compressible cakes and laminar (B) Incompressible cake and laminar (C) Compressible cake and turbulent (D) Incompressible cake and turbulent

Description : A straight line is obtained on plotting reciprocal of filtration rate vs. the volume of filtrate for __________ flow of filtrate. (A) Compressible cakes and laminar (B) Incompressible cake and laminar (C) Compressible cake and turbulent (D) Incompressible cake and turbulent

Last Answer : (B) Incompressible cake and laminar

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

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

Maximum heat transfer rate is achieved in __________ flow. (A) Co-current (B) Counter-current (C) Turbulent (D) Laminar

Description : Maximum heat transfer rate is achieved in __________ flow. (A) Co-current (B) Counter-current (C) Turbulent (D) Laminar

Last Answer : (C) Turbulen

Maximum heat transfer rate is obtained in __________ flow. (A) Laminar (B) Turbulent (C) Creeping (D) Transition region

Description : Maximum heat transfer rate is obtained in __________ flow. (A) Laminar (B) Turbulent (C) Creeping (D) Transition region

Last Answer : (B) Turbulent

Bernoulli's equation describes the (A) Mechanical energy balance in potential flow (B) Kinetic energy balance in laminar flow (C) Mechanical energy balance in turbulent flow (D) Mechanical energy balance in boundary layer

Description : Bernoulli's equation describes the (A) Mechanical energy balance in potential flow (B) Kinetic energy balance in laminar flow (C) Mechanical energy balance in turbulent flow (D) Mechanical energy balance in boundary layer

Last Answer : (A) Mechanical energy balance in potential flow

Fanning equation is given by (∆P/ρ) = 4f (L/D) (v 2 /2gc ). It is applicable to __________ region flow. (A) Transition (B) Laminar (C) Turbulent (D) Both (B) and (C)

Description : Fanning equation is given by (∆P/ρ) = 4f (L/D) (v 2 /2gc ). It is applicable to __________ region flow. (A) Transition (B) Laminar (C) Turbulent (D) Both (B) and (C)

Last Answer : (D) Both (B) and (C)

Transition from laminar flow to turbulent flow is aided by the (A) Surface roughness and curvature (i.e. sharp corners) (B) Vibration (C) Pressure gradient and the compressibility of the flowing medium (D) All (A), (B) & (C)

Description : Transition from laminar flow to turbulent flow is aided by the (A) Surface roughness and curvature (i.e. sharp corners) (B) Vibration (C) Pressure gradient and the compressibility of the flowing medium (D) All (A), (B) & (C)

Last Answer : (D) All (A), (B) & (C)

f = 16/NRe , is valid for (A) Turbulent flow (B) Laminar flow through an open channel(C) Steady flow(D) None of these

Description : f = 16/NRe , is valid for (A) Turbulent flow (B) Laminar flow through an open channel (C) Steady flow (D) None of these

Last Answer : (D) None of these

The distribution of shear stress in a stream of fluid in a circular tube is(A) Linear with radius for turbulent flow only(B) Linear with radius for laminar flow only(C) Linear with radius for both laminar & turbulent flow(D) Parabolic with radius for both laminar & turbulent flow

Description : The distribution of shear stress in a stream of fluid in a circular tube is (A) Linear with radius for turbulent flow only (B) Linear with radius for laminar flow only (C) Linear with radius for both laminar & turbulent flow (D) Parabolic with radius for both laminar & turbulent flow

Last Answer : (C) Linear with radius for both laminar & turbulent flow

Pick out the wrong statement. (A) A fluid mass is free from shearing forces, when it is made to rotate with a uniform velocity(B) Newton's law of viscosity is not applicable to the turbulent flow of fluidwith linear velocity distribution(C) Laminar flow of viscous liquids is involved in the lubrication of varioustypes of bearings(D) Rise of water in capillary tubes reduces with the increasing diameter ofcapillary tubes

Description : Pick out the wrong statement. (A) A fluid mass is free from shearing forces, when it is made to rotate with a uniform velocit (B) Newton's law of viscosity is not applicable to the ... types of bearings (D) Rise of water in capillary tubes reduces with the increasing diameter of capillary tubes

Last Answer : (B) Newton's law of viscosity is not applicable to the turbulent flow of fluid with linear velocity distribution

The laminar boundary layer thickness in zero pressure gradient flow over a flat plate along the x-direction varies as x0.5 while the thickness of turbulent boundary layer varies as (where, x = distance from the leading edge) (A) x1.5 (B) x0.8 (C) x-1.5 (D) x-0.8

Description : The laminar boundary layer thickness in zero pressure gradient flow over a flat plate along the x-direction varies as x0.5 while the thickness of turbulent boundary layer varies as (where, x = distance from the leading edge) (A) x1.5 (B) x0.8 (C) x-1.5 (D) x-0.8

Last Answer : (B) x0.8

Define : (i) Laminar flow (ii) Turbulent flow

Description : Define : (i) Laminar flow (ii) Turbulent flow

Last Answer : Laminar flow: - 1. Laminar flow occurs when the fluid flows in infinitesimal parallel layers with no disruption between them. For laminar flow Reynolds number Re < 2300 OR 2. The flow in which ... such a way that its velocity changes irregularly, such type of flow is known as turbulent flow. 

Compare i) Steady and uniform flow ii) Laminar and turbulent flow

Description : Compare i) Steady and uniform flow ii) Laminar and turbulent flow

Last Answer : Steady flow:- The flow is said to be steady when the flow characteristics, such as velocity, pressure, density and temperature do not change with time. Water flowing through a tap at a constant rate is an ... called as turbulent flow. e.g. The flow of river at the time of flood is turbulent flow.

Define laminar flow and turbulent flow.

Description : Define laminar flow and turbulent flow.

Last Answer : Laminar flow : When a fluid flowing through the pipe at different speeds (fast at center and slow at edges), and the fluid particles move in layers with one layer sliding over the adjacent ... successive cross sections, then this flow is called as turbulent flow. Reynolds no is greater than 4000 

During the opening of a valve in a pipe line, the flow is (A) Steady (B) Unsteady (C) Uniform (D) Laminar

Description : During the opening of a valve in a pipe line, the flow is (A) Steady (B) Unsteady (C) Uniform (D) Laminar

Last Answer : Answer: Option B

The loss of head due to viscosity for laminar flow in pipes is (where d = Diameter of pipe, l = Length of pipe, v w = Specific weight of the flowing liquid) (A) 4 (B) 8 (C) 16 (D) 32

Description : The loss of head due to viscosity for laminar flow in pipes is (where d = Diameter of pipe, l = Length of pipe, v w = Specific weight of the flowing liquid) (A) 4 (B) 8 (C) 16 (D) 32

Last Answer : Answer: Option D

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 centre of the pipe. 4. Hydraulic gradient varies as the square of the mean velocity of flow. Which of these statements are correct? (a) 1, 2 , 3 & 4 (b) 1 & 3 only (c) 2 & 4 only (d)3 & 4 only

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

Hydraulic mean depth (Dm) for a circular pipe of diameter 'D' flowing full is 0.25 D. For a circular channel, at Dm = 0.3 D, gives the condition for the maximum (A) Flow rate (B) Mean velocity (C) Both 'a' & 'b' (D) Neither 'a' nor 'b

Description : Hydraulic mean depth (Dm) for a circular pipe of diameter 'D' flowing full is 0.25 D. For a circular channel, at Dm = 0.3 D, gives the condition for the maximum (A) Flow rate (B) Mean velocity (C) Both 'a' & 'b' (D) Neither 'a' nor 'b

Last Answer : (B) Mean velocity

Nominal Pipe Size (NPS) of a pipe less than 12 inches in diameter indicates its(A) Inner diameter(B) Outer diameter(C) Thickness(D) Neither inner nor outer diameter

Description : Nominal Pipe Size (NPS) of a pipe less than 12 inches in diameter indicates its (A) Inner diameter (B) Outer diameter (C) Thickness (D) Neither inner nor outer diameter

Last Answer : (D) Neither inner nor outer diameter

For a given Reynold number as d/D for an orifice increases, Cd will (where, d & D are orifice & pipe diameters respectively). (A) Increase (B) Decrease (C) Remain constant (D) Either (A) or (B); depends on other factors

Description : For a given Reynold number as d/D for an orifice increases, Cd will (where, d & D are orifice & pipe diameters respectively). (A) Increase (B) Decrease (C) Remain constant (D) Either (A) or (B); depends on other factors

Last Answer : (A) Increase

. 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 increasing Reynolds number (C) Point of maximum instability exists at a distance of 2r/3 from the pipe wall (r = pipe radius) (D) Skin friction drag, shear stresses, random orientation of fluid particles and slope of velocity profile at the wall are more

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

Nusselt number for full developed, laminar, constant property flow in a pipe at uniform heat flux is (A) 0.72 (B) 4.364 (C) 18 (D) 83

Description : Nusselt number for full developed, laminar, constant property flow in a pipe at uniform heat flux is (A) 0.72 (B) 4.364 (C) 18 (D) 83

Last Answer : (B) 4.364