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

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
by

1 Answer

Answer :

(B) NPr
1/3
by

Related questions

. If Prandtl number is greater than the Schmidt number, then the (A) Thermal boundary layer lies inside the concentration boundary layer (B) Concentration boundary layer lies inside the thermal boundary layer (C) Thermal & concentration boundary layers are of equal thickness (D) Hydrodynamic (i.e., momentum) boundary layer is thicker than the other two

Description : . If Prandtl number is greater than the Schmidt number, then the (A) Thermal boundary layer lies inside the concentration boundary layer (B) Concentration boundary layer lies inside the thermal boundary ... (D) Hydrodynamic (i.e., momentum) boundary layer is thicker than the other two

Last Answer : (A) Thermal boundary layer lies inside the concentration boundary layer

Thickness of thermal boundary layer is more compared to that of hydrodynamic boundary layer, when the value of Prandtl number is (A) 1 (B) < 1 (C) > 1 (D) > 5

Description : Thickness of thermal boundary layer is more compared to that of hydrodynamic boundary layer, when the value of Prandtl number is (A) 1 (B) < 1 (C) > 1 (D) > 5

Last Answer : (B) < 1

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

At what value of Prandtl number, the hydrodynamic and thermal boundary layers of a fluid flowing over a heated plate will be identical? (A) 1 (B) < 1 (C) > 1 (D) None of these

Description : At what value of Prandtl number, the hydrodynamic and thermal boundary layers of a fluid flowing over a heated plate will be identical? (A) 1 (B) < 1 (C) > 1 (D) None of these

Last Answer : (A) 1

The thermal boundary layer at NPr > 1 (A) Is thicker than hydrodynamic boundary layer (B) Is thinner than hydrodynamic boundary layer (C) And the hydrodynamic boundary layers are identical (D) Disappears

Description : The thermal boundary layer at NPr > 1 (A) Is thicker than hydrodynamic boundary layer (B) Is thinner than hydrodynamic boundary layer (C) And the hydrodynamic boundary layers are identical (D) Disappears

Last Answer : (B) Is thinner than hydrodynamic boundary layer

The ratio of hydrodynamic boundary layer to thermal boundary layer thickness in case of liquid metals is (A) < 1 (B) 1 (C) > 1 (D) 2

Description : The ratio of hydrodynamic boundary layer to thermal boundary layer thickness in case of liquid metals is (A) < 1 (B) 1 (C) > 1 (D) 2

Last Answer : (A) < 1

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

The hydrodynamic and thermal boundary layers will merge, when (A) Prandtl number is one (B) Schmidt number tends to infinity (C) Nusselt number tends to infinity (D) Archimedes number is greater than 10000

Description : The hydrodynamic and thermal boundary layers will merge, when (A) Prandtl number is one (B) Schmidt number tends to infinity (C) Nusselt number tends to infinity (D) Archimedes number is greater than 10000

Last Answer : (A) Prandtl number is one

How the thickness of thermal boundary layer and thickness of hydrodynamic boundary layer related ?

Description : How the thickness of thermal boundary layer and thickness of hydrodynamic boundary layer related ?

Last Answer : Ratio of their thickness = (Prandtl number)-1/3.

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

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

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

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

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

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

The equation, Nst = (f/2)/[1 + 5 (Npr - 1) √(f/2)], corresponds to __________ analogy. (A) Von-Karman (B) Reynolds (C) Colburn (D) Prandtl

Description : The equation, Nst = (f/2)/[1 + 5 (Npr - 1) √(f/2)], corresponds to __________ analogy. (A) Von-Karman (B) Reynolds (C) Colburn (D) Prandtl

Last Answer : (D) Prandtl

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

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

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

A composite flat wall of a furnace is made of two materials 'A' and 'B'. The thermal conductivity of 'A' is twice of that of material 'B', while the thickness of layer of 'A' is half that of B. If the temperature at the two sides of the wall are 400 and 1200°K, then the temperature drop (in °K) across the layer of material 'A' is (A) 125 (B) 133 (C) 150 (D) 160

Description : A composite flat wall of a furnace is made of two materials 'A' and 'B'. The thermal conductivity of 'A' is twice of that of material 'B', while the thickness of layer of 'A' is half that of B. If the temperature ... drop (in °K) across the layer of material 'A' is (A) 125 (B) 133 (C) 150 (D) 160

Last Answer : (D) 160

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

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

When the ratio of the Grashoff number and to the square of Reynolds number is one, the dominant mechanism of heat transfer is: (A) Free convection (B) Entry length problem in laminar forced conduction (developing thermal boundary layer) (C) Mixed convection (both free and forced) (D) Forced convection

Description : When the ratio of the Grashoff number and to the square of Reynolds number is one, the dominant mechanism of heat transfer is: (A) Free convection (B) Entry length problem in laminar forced ... (developing thermal boundary layer) (C) Mixed convection (both free and forced) (D) Forced convection

Last Answer : (C) Mixed convection (both free and forced)

Pick out the wrong statement. (A) The mass diffusivity, the thermal diffusivity and the eddy momentum diffusivity are the same for NSc = NPr= 1 (B) 1 Nm3 of dry air is lighter than 1Nm3 of humid air (C) The Lewis number of a mixture is unity, when the thermal diffusivity is equal to the mass diffusivity

Description : Pick out the wrong statement. (A) The mass diffusivity, the thermal diffusivity and the eddy momentum diffusivity are the same for NSc = NPr= 1 (B) 1 Nm3 of dry air is lighter ... ) The Lewis number of a mixture is unity, when the thermal diffusivity is equal to the mass diffusivity

Last Answer : (B) 1 Nm3 of dry air is lighter than 1Nm3 of humid air

Prandtl number is the ratio of (A) Mass diffusivity to thermal diffusivity (B) Momentum diffusivity to thermal diffusivity (C) Thermal diffusivity to mass diffusivity (D) Thermal diffusivity to momentum diffusivity

Description : Prandtl number is the ratio of (A) Mass diffusivity to thermal diffusivity (B) Momentum diffusivity to thermal diffusivity (C) Thermal diffusivity to mass diffusivity (D) Thermal diffusivity to momentum diffusivity

Last Answer : (B) Momentum diffusivity to thermal diffusivity

The ratio of momentum diffusivity to thermal diffusivity is the __________ number. (A) Prandtl (B) Nusselt (C) Stanton (D) Grashoff

Description : The ratio of momentum diffusivity to thermal diffusivity is the __________ number. (A) Prandtl (B) Nusselt (C) Stanton (D) Grashoff

Last Answer : (A) Prandtl

The ratio of kinematic viscosity to thermal diffusivity is called the __________ number. (A) Peclet (B) Prandtl (C) Stanton (D) Nusselt

Description : The ratio of kinematic viscosity to thermal diffusivity is called the __________ number. (A) Peclet (B) Prandtl (C) Stanton (D) Nusselt

Last Answer : (B) Prandtl

Prandtl number is the ratio of (A) Momentum diffusivity to mass diffusivity (B) Momentum diffusivity to thermal diffusivity (C) Thermal diffusivity to mass diffusivity (D) Thermal diffusivity to momentum diffusivity

Description : Prandtl number is the ratio of (A) Momentum diffusivity to mass diffusivity (B) Momentum diffusivity to thermal diffusivity (C) Thermal diffusivity to mass diffusivity (D) Thermal diffusivity to momentum diffusivity

Last Answer : (B) Momentum diffusivity to thermal diffusivity

Boundary layer separation is caused by the (A) Reduction of pressure to vapour pressure (B) Boundary layer thickness reducing to zero (C) Adverse pressure gradient (D) Reduction of pressure gradient to zero

Description : Boundary layer separation is caused by the (A) Reduction of pressure to vapour pressure (B) Boundary layer thickness reducing to zero (C) Adverse pressure gradient (D) Reduction of pressure gradient to zero

Last Answer : (D) Reduction of pressure gradient to zero

Boundary layer separation is caused by the (A) Reduction of pressure below vapour pressure (B) Reduction of pressure gradient to zero (C) Adverse pressure gradient (D) Reduction of boundary layer thickness to zero

Description : Boundary layer separation is caused by the (A) Reduction of pressure below vapour pressure (B) Reduction of pressure gradient to zero (C) Adverse pressure gradient (D) Reduction of boundary layer thickness to zero

Last Answer : (C) Adverse pressure gradient

Starting friction is low in case of the __________ lubrication. (A) Boundary (B) Hydrodynamic (C) Hydrostatic (D) Mixed/semi-fluid

Description : Starting friction is low in case of the __________ lubrication. (A) Boundary (B) Hydrodynamic (C) Hydrostatic (D) Mixed/semi-fluid

Last Answer : (C) Hydrostatic

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 mass diffusivity, the thermal diffusivity and the eddy momentum diffusivity are same for, NPr = NSc = __________ (A) 1 (B) 0.5 (C) 10 (D) 0

Description : The mass diffusivity, the thermal diffusivity and the eddy momentum diffusivity are same for, NPr = NSc = __________ (A) 1 (B) 0.5 (C) 10 (D) 0

Last Answer : (A) 1

Fluid motion in the natural convection heat transfer between a solid surface and a fluid in contact with it, results from the (A) Existence of thermal boundary layer (B) Temperature gradient produced due to density difference (C) Buoyancy of the bubbles produced at active nucleation site (D) None of these

Description : Fluid motion in the natural convection heat transfer between a solid surface and a fluid in contact with it, results from the (A) Existence of thermal boundary layer (B) Temperature gradient produced ... difference (C) Buoyancy of the bubbles produced at active nucleation site (D) None of these

Last Answer : (D) None of these

Conductance is given by (where, x = thickness, A = heat flow area, K = thermal conductivity.) (A) x/KA (B) KA/x (C) K/Ax (D) A/Kx

Description : Conductance is given by (where, x = thickness, A = heat flow area, K = thermal conductivity.) (A) x/KA (B) KA/x (C) K/Ax (D) A/Kx

Last Answer : (B) KA/x

Boundary lubricated bearing is (A) Thick film bearing (B) Thin film bearing (C) Hydrodynamic bearing (D) Hydrostatic bearing

Description : Boundary lubricated bearing is (A) Thick film bearing (B) Thin film bearing (C) Hydrodynamic bearing (D) Hydrostatic bearing

Last Answer : (B) Thin film bearing

A wall has two layers of materials A and B; each made of a different material. Both the layers have the same thickness. The thermal conductivity of material A is twice that of B. Under the equilibrium, the temperature difference across the wall is 36°C. The temperature difference across the layer A is __________ °C. (A) 6 (B) 12 (C) 18 (D) 24

Description : A wall has two layers of materials A and B; each made of a different material. Both the layers have the same thickness. The thermal conductivity of material A is twice that of B. Under the equilibrium, the temperature ... difference across the layer A is __________ °C. (A) 6 (B) 12 (C) 18 (D) 24

Last Answer : (B) 12

A furnace is made of a refractory brick wall of thickness 0.5 metre and thermal conductivity 0.7 W/m.°K For the same temperature drop and heat loss, this refractory wall can be replaced by a layer of diatomaceous earth of thermal conductivity 0.14 W/m.K and thickness __________ metre. (A) 0.01 (B) 0.1 (C) 0.25 (D) 0.5

Description : A furnace is made of a refractory brick wall of thickness 0.5 metre and thermal conductivity 0.7 W/m.°K For the same temperature drop and heat loss, this refractory wall can be replaced by a layer of diatomaceous earth of ... and thickness __________ metre. (A) 0.01 (B) 0.1 (C) 0.25 (D) 0.5

Last Answer : (B) 0.1

Dittus-Boelter equation cannot be used for molten metals mainly due to its very low (A) Prandtl number (B) Grashoff number (C) Thermal conductivity (D) Viscosity

Description : Dittus-Boelter equation cannot be used for molten metals mainly due to its very low (A) Prandtl number (B) Grashoff number (C) Thermal conductivity (D) Viscosity

Last Answer : (A) Prandtl number

Prandtl number is the reciprocal of (A) Thermal diffusivity/Momentum diffusivity (B) Thermal diffusivity × Momentum (C) Thermal diffusivity × Mass diffusivity (D) Mass diffusivity × Momentum diffusivity

Description : Prandtl number is the reciprocal of (A) Thermal diffusivity/Momentum diffusivity (B) Thermal diffusivity × Momentum (C) Thermal diffusivity × Mass diffusivity (D) Mass diffusivity × Momentum diffusivity

Last Answer : (A) Thermal diffusivity/Momentum diffusivity

A journal bearing with hydrodynamic lubrication is running steadily with a certain amount of minimum film thickness. When the load and speed are doubled, how does the minimum film thickness vary? [IES-2008] (a) Remains unchanged (b) Gets doubled (c) Gets reduced to one-fourth of original value (d) Gets reduced to half of original value

Description : A journal bearing with hydrodynamic lubrication is running steadily with a certain amount of minimum film thickness. When the load and speed are doubled, how does the minimum film thickness vary? [IES-2008 ... Gets reduced to one-fourth of original value (d) Gets reduced to half of original value

Last Answer : (a) Remains unchanged

In hydrodynamic lubrication, film thickness remains unaffected by change in speeds. a) True b) Increase with increase in speed c) Decrease with increase in speed d) Disappear as the speed tends to infinty

Description : In hydrodynamic lubrication, film thickness remains unaffected by change in speeds. a) True b) Increase with increase in speed c) Decrease with increase in speed d) Disappear as the speed tends to infinty

Last Answer : b) Increase with increase in speed

Direct conversion of thermal energy to electrical energy is facilitated by the (A) Fuel cells (B) Photo voltaic cell (C) Magneto hydrodynamic generator (D) None of these

Description : Direct conversion of thermal energy to electrical energy is facilitated by the (A) Fuel cells (B) Photo voltaic cell (C) Magneto hydrodynamic generator (D) None of these

Last Answer : (C) Magneto hydrodynamic generator

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

Pick out the wrong statement. (A) Reciprocal of the resistance to heat flow is called thermal conductance (B) Unit of thermal conductance is W/°K (C) Thermal conductance of a wall of thickness 'L', thermal conductivity 'k' and heat flow area 'A' is kL/A (D) None of these

Description : Pick out the wrong statement. (A) Reciprocal of the resistance to heat flow is called thermal conductance (B) Unit of thermal conductance is W/°K (C) Thermal conductance of a wall of thickness 'L', thermal conductivity 'k' and heat flow area 'A' is kL/A (D) None of these

Last Answer : (C) Thermal conductance of a wall of thickness 'L', thermal conductivity 'k' and heat flow area 'A' is kL/A

NSc /NPr is called the (A) Psychrometric ratio (B) Lewis number (C) Sherwood number (D) Stanton number

Description : NSc /NPr is called the (A) Psychrometric ratio (B) Lewis number (C) Sherwood number (D) Stanton number

Last Answer : (B) Lewis number

Pick out the wrong statement. (A) Fluid movement under the influence of buoyant forces resulting from change in density takes place in case of natural convection (B) The ratio NNu /NRe . Npr is called the Stanton number (C) The Peclet number is a measure of the ratio of energy transport by convection to that by conduction (D) The Colburn jH factor for heat transfer is given by Nst Npr

Description : Pick out the wrong statement. (A) Fluid movement under the influence of buoyant forces resulting from change in density takes place in case of natural convection (B) The ratio NNu /NRe . Npr is ... convection to that by conduction (D) The Colburn jH factor for heat transfer is given by Nst Npr

Last Answer : (D) The Colburn jH factor for heat transfer is given by Nst Npr

Pick out the wrong statement. (A) Seam welding, projection welding & spot welding are the classification of electrical resistance welding (B) Electrode tip in spot welding is of copper and the tip diameter should be equal to t (where, t = plate thickness to be welded) (C) In spot welding, two pieces to be joined are overlapped and placed between two electrodes (D) Mild steel sheet cannot be spot welded

Description : Pick out the wrong statement. (A) Seam welding, projection welding & spot welding are the classification of electrical resistance welding (B) Electrode tip in spot welding is of copper and the ... joined are overlapped and placed between two electrodes (D) Mild steel sheet cannot be spot welded

Last Answer : (D) Mild steel sheet cannot be spot welded

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

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