Boundary layer exists in flow (A) Of real fluids (B) Over flat surfaces only (C) In pipes only (D) Of ideal fluids only

Boundary layer exists in flow
(A) Of real fluids
(B) Over flat surfaces only
(C) In pipes only
(D) Of ideal fluids only
by

1 Answer

Answer :

(A) Of real fluids
by

Related questions

Steady state one dimensional heat flow by conduction as given by Fourier's low does not assume that (A) There is no internal heat generation (B) Boundary surfaces are isothermal (C) Material is anisotropic (D) Constant temperature gradient exists

Description : Steady state one dimensional heat flow by conduction as given by Fourier's low does not assume that (A) There is no internal heat generation (B) Boundary surfaces are isothermal (C) Material is anisotropic (D) Constant temperature gradient exists

Last Answer : (C) Material is anisotropic

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)

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)

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 boundary. (V) Fluid cannot penetrate a boundary. (A) I, II, III (B) II, III, V (C) I, II, V (D) II, IV, V

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

For flow over a flat plate, the ratio of thermal boundary layer thickness, 'xt' and hydrodynamic boundary layer thickness 'x' is equal to (where, NPr = Prandtl number) (A) NPr (B) NPr 1/3 (C) NPr -1 (D) NPr -1/3

Description : For flow over a flat plate, the ratio of thermal boundary layer thickness, 'xt' and hydrodynamic boundary layer thickness 'x' is equal to (where, NPr = Prandtl number) (A) NPr (B) NPr 1/3 (C) NPr -1 (D) NPr -1/3

Last Answer : (B) NPr 1/3

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

For flow past a flat plate, if ‘x’ is the distance along the plate in the direction of flow, the boundary layer thickness is proportional to (A) √x (B) 1/√x (C) x (D) 1/x Answe

Description : For flow past a flat plate, if ‘x’ is the distance along the plate in the direction of flow, the boundary layer thickness is proportional to (A) √x (B) 1/√x (C) x (D) 1/x Answe

Last Answer : (A) √x

At the point of boundary layer separation in fluid flow, the (A) Shear stress is maximum (B) Velocity gradient is flat (C) Density variation is maximum (D) Shear stress is zero

Description : At the point of boundary layer separation in fluid flow, the (A) Shear stress is maximum (B) Velocity gradient is flat (C) Density variation is maximum (D) Shear stress is zero

Last Answer : Option A

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

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

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 first fluid, the pressure drop will (A) Increase (B) Decrease (C) Remain unchanged (D) Data insufficient to predict relative pressure drop

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

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

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

An ideal flow of any fluid must satisfy (A) Pascal law (B) Newton's law of viscosity (C) Boundary layer theory (D) Continuity equation

Description : An ideal flow of any fluid must satisfy (A) Pascal law (B) Newton's law of viscosity (C) Boundary layer theory (D) Continuity equation

Last Answer : Answer: Option D

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

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

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 through two fluids where there is a surface of discontinuity, gravity forces, and wave making effect, as with ship's hulls (D) All of the above

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

Last Answer : Answer: Option C

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 through two fluids where there is a surface of discontinuity, gravity forces, and wave making effect, as with ship's hulls (D) All of the above

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

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 two fluids where there is a surface of discontinuity, gravity force, and wave making effects, as with ship's hulls (D) All of the above

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

Last Answer : Answer: Option A

Pick out the wrong statement. (A) In the McCabe-Thiele diagram for binary distillation, vertical feed line represents saturated liquid feed and horizontal feed line represents saturated vapour feed (B) In small columns, local efficiency is larger than Murphree efficiency; in large columns local efficiency is smaller than Murphree efficiency (C) For Laminar flow over a plate of length L, the local mass transfer co￾efficient at a distance L from the leading edge is 1.5 × 10 -2m/s. Then the average mass transfer co-efficient for the plate is 2 × 10 -2m/s (D) The concentration and hydrodynamic boundary layers over a flat plate are of equal thickness, if Schmidt number is equal to unity

Description : Pick out the wrong statement. (A) In the McCabe-Thiele diagram for binary distillation, vertical feed line represents saturated liquid feed and horizontal feed line represents saturated vapour feed (B) In ... layers over a flat plate are of equal thickness, if Schmidt number is equal to unity

Last Answer : (C) For Laminar flow over a plate of length L, the local mass transfer co￾efficient at a distance L from the leading edge is 1.5 × 10 -2m/s. Then the average mass transfer co-efficient for the plate is 2 × 10 -2m/s

The thickness of a laminar boundary layer over a flat plate at two different sections P and Q are 0.8 cm and 2.4 cm respectively. If the section Q is 3.6 m downstream of P, the distance of section P from the leading edge of the plate is (a) 0.32 m (b) 0.22 m (c) 0.40 m (d) 0.53 m

Description : The thickness of a laminar boundary layer over a flat plate at two different sections P and Q are 0.8 cm and 2.4 cm respectively. If the section Q is 3.6 m downstream of P, the distance of section P from the leading edge of the plate is (a) 0.32 m (b) 0.22 m (c) 0.40 m (d) 0.53 m

Last Answer : Ans: (c) Correct Answer is: 0.45 m

What is the ratio of displacement thickness to nominal thickness for a linear distribution of velocity in the boundary layer on a flat plate? (A) 0.5 (B) 1 (C) 1.5 (D) 2

Description : What is the ratio of displacement thickness to nominal thickness for a linear distribution of velocity in the boundary layer on a flat plate? (A) 0.5 (B) 1 (C) 1.5 (D) 2

Last Answer : (A) 0.5

The boundary layer thickness at a given section along a flat plate __________ with increasing Reynold's number(A) Increases(B) Decreases(C) Remain same(D) May increase or decrease.

Description : The boundary layer thickness at a given section along a flat plate __________ with increasing Reynold's number. (A) Increases (B) Decreases (C) Remain same (D) May increase or decrease

Last Answer : (B) Decreases

An ideal nozzle design aims at (A) Minimising wall friction (B) Suppressing boundary layer separation (C) Both (A) & (B) (D) Neither (A) nor (B)

Description : An ideal nozzle design aims at (A) Minimising wall friction (B) Suppressing boundary layer separation (C) Both (A) & (B) (D) Neither (A) nor (B)

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

Pick out the wrong statement: (A) Chemical reactions with high activation energy are very temperature sensitive (B) A flat velocity profile exists in a plug flow reactor (C) The residence time for all the elements of fluid in case of a P.F.R. need not be same (D) Half life of a reaction increases with increased initial concentration for reaction orders more than one

Description : Pick out the wrong statement: (A) Chemical reactions with high activation energy are very temperature sensitive (B) A flat velocity profile exists in a plug flow reactor (C) The residence ... D) Half life of a reaction increases with increased initial concentration for reaction orders more than one

Last Answer : (C) The residence time for all the elements of fluid in case of a P.F.R. need not be same

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 of capillarity in water (c) Cavitation results from the action of very high pressure (d) Real fluids have lower viscosity than ideal fluids

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

The continuity equation in ideal fluid flow states that (A) Net rate of inflow into any small volume must be zero (B) Energy is not constant along a streamline (C) Energy is constant along a streamline (D) There exists a velocity potential

Description : The continuity equation in ideal fluid flow states that (A) Net rate of inflow into any small volume must be zero (B) Energy is not constant along a streamline (C) Energy is constant along a streamline (D) There exists a velocity potential

Last Answer : (A) Net rate of inflow into any small volume must be zero

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

Boundary layer separation is characterised by one of the conditions given below, where 'Re' is the Reynolds number for the flow. Select the appropriate conditions. (A) Re << 1, accelerating flow (B) Re >> 1, accelerating flow (C) Re << 1, decelerating flow (D) Re >>1, decelerating flow

Description : Boundary layer separation is characterised by one of the conditions given below, where 'Re' is the Reynolds number for the flow. Select the appropriate conditions. (A) Re > 1, accelerating flow (C) Re >1, decelerating flow

Last Answer : (D) Re >>1, decelerating flow

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 these

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

Pick out the wrong statement: (A) Greater is the kinematic viscosity of the liquid, greater is the thickness of the boundary layer (B) Blowers develop a maximum pressure of 2 atmospheres (C) Friction losses in pipe fittings are generally expressed in terms of velocity heads (D) Fanning friction factor in case of turbulent flow of liquids in pipe depends upon relative roughness & Reynolds number

Description : Pick out the wrong statement: (A) Greater is the kinematic viscosity of the liquid, greater is the thickness of the boundary layer (B) Blowers develop a maximum pressure of 2 atmospheres ( ... factor in case of turbulent flow of liquids in pipe depends upon relative roughness & Reynolds number

Last Answer : (C) Friction losses in pipe fittings are generally expressed in terms of velocity heads

The length of the tube necessary for the boundary layer to reach thecentre of the tube and for fully developed flow to be established is called the__________ length.(A) Equivalent(B) Transition(C) Prandtl mixing(D) None of these

Description : The length of the tube necessary for the boundary layer to reach thecentre of the tube and for fully developed flow to be established is called the __________ length. (A) Equivalent (B) Transition (C) Prandtl mixing (D) None of these

Last Answer : (B) Transition

__________ flow means the flow of incompressible fluid with no shear. (A) Potential (B) Streamline (C) Creep (D) Boundary layer

Description : __________ flow means the flow of incompressible fluid with no shear. (A) Potential (B) Streamline (C) Creep (D) Boundary layer

Last Answer : (A) Potential

Existence of boundary layer in fluid flow is because of the (A) Surface tension (B) Fluid density (C) Fluid viscosity (D) Gravity forces

Description : Existence of boundary layer in fluid flow is because of the (A) Surface tension (B) Fluid density (C) Fluid viscosity (D) Gravity forces

Last Answer : (C) Fluid viscosity

The boundary layer is that part of a moving fluid, in which the fluid velocity is (A) Affected by the fluid flow pressure (B) Constant(C) Affected by the presence of a solid boundary(D) All (A), (B) and (C)

Description : The boundary layer is that part of a moving fluid, in which the fluid velocity is (A) Affected by the fluid flow pressure (B) Constant (C) Affected by the presence of a solid boundary (D) All (A), (B) and (C)

Last Answer : (C) Affected by the presence of a solid boundary

The major reason of hydrodynamic noise (i.e., noise resulting from liquid flow) is (A) Pipe vibrations (B) Cavitation (C) Boundary layer separation (D) Fluctuation in liquid flow

Description : The major reason of hydrodynamic noise (i.e., noise resulting from liquid flow) is (A) Pipe vibrations (B) Cavitation (C) Boundary layer separation (D) Fluctuation in liquid flow

Last Answer : (B) Cavitation

In a boundary layer developed along the flow, the pressure decreases in the downstream direction. The boundary layer thickness in this case will (A) Decrease gradually (B) Increase gradually (C) Increase rapidly (D) Remain constant

Description : In a boundary layer developed along the flow, the pressure decreases in the downstream direction. The boundary layer thickness in this case will (A) Decrease gradually (B) Increase gradually (C) Increase rapidly (D) Remain constant

Last Answer : (B) Increase gradually

Which of the following statements is TRUE for an ideal gas, but not for a real gas?  A. PV = nRT  B. An increase in temperature causes an increase in the kinetic energy of the gas  C. The total volume of molecules on a gas is nearly the same as the volume of the gas as a whole  D. No attractive forces exists between the molecule of a gas

Description : Which of the following statements is TRUE for an ideal gas, but not for a real gas?  A. PV = nRT  B. An increase in temperature causes an increase in the kinetic energy of the gas  C. The ... same as the volume of the gas as a whole  D. No attractive forces exists between the molecule of a gas

Last Answer : PV = nRT

The nature of loading at various locations and other surfaces conditions called a.friction b.traction c.boundary condition d.surfacing

Description : The nature of loading at various locations and other surfaces conditions called a.friction b.traction c.boundary condition d.surfacing

Last Answer : c.boundary condition

02. The separation of flow occurs when the hydrodynamic boundary layer thickness is reduced to zero. A) AgreeB) Disagree

Description : 02. The separation of flow occurs when the hydrodynamic boundary layer thickness is reduced to zero. A) Agree B) Disagree

Last Answer : A

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

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

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

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

When describing image formation for flat shiny surfaces what is an important rule to remember about light rays?

Description : When describing image formation for flat shiny surfaces what is an important rule to remember about light rays?

Last Answer : The angle when it leaves is the same as the angle when it hits

Are the faces of a polyhedron all flat surfaces?

Description : Are the faces of a polyhedron all flat surfaces?

Last Answer : Yes and its flat surface faces are in regular shapes.

Are polyhedrons are made up of flat surfaces?

Description : Are polyhedrons are made up of flat surfaces?

Last Answer : Yes and the flat surfaces are called faces

Why does calcite break smooth flat surfaces?

Description : Why does calcite break smooth flat surfaces?

Last Answer : calcite has a regular arrangement of atoms.

What shapes has 0 vertices and 2 flat surfaces?

Description : What shapes has 0 vertices and 2 flat surfaces?

Last Answer : Feel Free to Answer

Why does calcite break smooth flat surfaces?

Description : Why does calcite break smooth flat surfaces?

Last Answer : calcite has a regular arrangement of atoms.

What is he required surface finish for raised or flat faced gasket surfaces? a) 63 µ in. b) 125 µ in-250 µ in. c) 250 µ in-400 µ in. d) 400-500 µ in.

Description : What is he required surface finish for raised or flat faced gasket surfaces? a) 63 µ in. b) 125 µ in-250 µ in. c) 250 µ in-400 µ in. d) 400-500 µ in.

Last Answer : b) 125 µ in-250 µ in.

Two perspective views of the same solid object are shown below. How many surfaces does the object contain? Assume hidden surfaces to be flat.

Description : Two perspective views of the same solid object are shown below. How many surfaces does the object contain? Assume hidden surfaces to be flat.   

Last Answer : 18

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

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

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

When both the fluids flow concurrently in an absorber, the slope of the operating line is (A) -ve (B) +ve (C) 1 (D) -1

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

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

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