Stoke's law is valid, when NRe, p is less than (A) 2 (B) 100 (C) 2100 (D) 700

Stoke's law is valid, when NRe, p
is less than
(A) 2
(B) 100
(C) 2100
(D) 700
by

1 Answer

Answer :

(A) 2
by

Related questions

A fluid (µ/ρ) = 0.01 cm2 /sec is moving at critical flow condition (NRe = 2100) through a pipe of dia 3 cms. Velocity of flow is __________ cm/sec. (A) 7 (B) 700 (C) 7000 (D) 630

Description : A fluid (µ/ρ) = 0.01 cm2 /sec is moving at critical flow condition (NRe = 2100) through a pipe of dia 3 cms. Velocity of flow is __________ cm/sec. (A) 7 (B) 700 (C) 7000 (D) 630

Last Answer : (A) 7

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

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

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

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

Friction factor for a hydraulically smooth pipe at NRe = 2100 is f1 . If the pipe is further smoothened (i.e., roughness is reduced), the friction factor at the same value of NRe , will (A) Increase (B) Decrease (C) Remain unchanged (D) Increase or decrease depending on the pipe material

Description : Friction factor for a hydraulically smooth pipe at NRe = 2100 is f1 . If the pipe is further smoothened (i.e., roughness is reduced), the friction factor at the same value of NRe , will (A) Increase (B) Decrease (C) Remain unchanged (D) Increase or decrease depending on the pipe material

Last Answer : (A) Increase

Stoke's law is valid only if the size of particle is (A) Less than 0.0002 mm (B) Greater than 0.2 mm (C) Between 0.2 mm and 0.0002 mm (D) All of the above

Description : Stoke's law is valid only if the size of particle is (A) Less than 0.0002 mm (B) Greater than 0.2 mm (C) Between 0.2 mm and 0.0002 mm (D) All of the above

Last Answer : Answer: Option C

Stoke's equation is valid in the Reynolds number range (A) 0.01 to 0.1 (B) 0.1 to 2 (C) 2 to 10 (D) 10 to 100

Description : Stoke's equation is valid in the Reynolds number range (A) 0.01 to 0.1 (B) 0.1 to 2 (C) 2 to 10 (D) 10 to 100

Last Answer : (A) 0.01 to 0.1

Stoke's law is valid, when the particle Reynolds number is (A) < 1 (B) > 1 (C) < 5 (D) None of these

Description : Stoke's law is valid, when the particle Reynolds number is (A) < 1 (B) > 1 (C) < 5 (D) None of these

Last Answer : (A) < 1

For the Stoke's law to be valid in the case of a falling sphere in a fluid, the (A) Reynolds number (based on sphere diameter) should be < 1 (B) Flow around the sphere should be in turbulent region (C) Sphere must be metallic (D) Fluid density should be constant

Description : For the Stoke's law to be valid in the case of a falling sphere in a fluid, the (A) Reynolds number (based on sphere diameter) should be < 1 (B) Flow around the sphere should be in turbulent region (C) Sphere must be metallic (D) Fluid density should be constant

Last Answer : (C) Sphere must be metallic

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

?% of 725 + 14% of 2100 = 700 a) 64 b) 80 c) 72 d) 56 e) 48

Description : ?% of 725 + 14% of 2100 = 700 a) 64 b) 80 c) 72 d) 56 e) 48

Last Answer : ?% × 725 +14 × 21=700 =>?% × 725 +294 =700 => ?% × 725 =406 =>?=406/725 × 100 =56 Answer: d)

Heat transfer co-efficient equation for forced convection, Nu = 0.023 Re 0.8 . Pr n , is not valid, if the value of (A) n = 0.4 is used for heating (B) n = 0.3 is used for cooling (C) Reynolds number for the flow involved is > 10000 (D) Reynolds number for the flow involved is < 2100

Description : Heat transfer co-efficient equation for forced convection, Nu = 0.023 Re 0.8 . Pr n , is not valid, if the value of (A) n = 0.4 is used for heating (B) n = 0.3 is used for cooling (C) Reynolds number for the flow involved is > 10000 (D) Reynolds number for the flow involved is < 2100

Last Answer : (D) Reynolds number for the flow involved is < 2100

When a vector is irrotational, which condition holds good? a) Stoke’s theorem gives non-zero value b) Stoke’s theorem gives zero value c) Divergence theorem is invalid d) Divergence theorem is valid

Description : When a vector is irrotational, which condition holds good? a) Stoke’s theorem gives non-zero value b) Stoke’s theorem gives zero value c) Divergence theorem is invalid d) Divergence theorem is valid

Last Answer : b) Stoke’s theorem gives zero value

If G is the specific gravity of particles of diameter d, the velocity of settlement V in still water at T°C, according to Stoke's law, is (A) V = 418 (G - 1) d² [(3T + 70)/100] (B) V = 418 (G - 1) d [(3T - 70)/100] (C) V = 418 (G - 1) d² [(2T + 70)/100] (D) V = 418 (G - 1) d 4 [(3T + 70)/100]

Description : If G is the specific gravity of particles of diameter d, the velocity of settlement V in still water  at T°C, according to Stoke's law, is  (A) V = 418 (G - 1) d² [(3T + 70)/100]  (B) V = 418 (G - 1) d [(3T - ... 1) d² [(2T + 70)/100]  (D) V = 418 (G - 1) d 4  [(3T + 70)/100] 

Last Answer : (A) V = 418 (G - 1) d² [(3T + 70)/100] 

It is desired to concentrate a 20% salt solution (20 kg of salt in 100 kg of solution) to a 30% salt solution in an evaporator. Consider a feed of 300 kg/min at 30°C. The boiling point of the solution is 110°C, the latent heat of vaporisation is 2100 kJ/kg and the specific heat of the solution is 4 kJ/kg.K. The rate at which the heat has to be supplied in (kJ/min) to the evaporator is (A) 3.06 × 10 5 (B) 6.12 × 10 5 (C) 7.24 × 10 5 (D) 9.08 × 10

Description : It is desired to concentrate a 20% salt solution (20 kg of salt in 100 kg of solution) to a 30% salt solution in an evaporator. Consider a feed of 300 kg/min at 30°C. The boiling point of the solution is 110°C, the latent heat of ... 3.06 10 5 (B) 6.12 10 5 (C) 7.24 10 5 (D) 9.08 10

Last Answer : (A) 3.06 × 10

For an ideal fluid flow, Reynolds number is (A) 2100 (B) 100 (C) 0 (D) ∞

Description : For an ideal fluid flow, Reynolds number is (A) 2100 (B) 100 (C) 0 (D) ∞

Last Answer : (D) ∞

Capillary tube method of viscosity measurement is based on the (A) Hagen-Poiseuille’s equation (B) Stoke's law (C) Navier-stokes equation (D) None of these

Description : Capillary tube method of viscosity measurement is based on the (A) Hagen-Poiseuille’s equation (B) Stoke's law (C) Navier-stokes equation (D) None of these

Last Answer : (A) Hagen-Poiseuille’s equation

The Navier-Stokes equation deals with the law of conservation of (A) Mass (B) Energy (C) Both (A) & (B) (D) Momentum

Description : The Navier-Stokes equation deals with the law of conservation of (A) Mass (B) Energy (C) Both (A) & (B) (D) Momentum

Last Answer : (D) Momentum

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

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

The ratio of wall drag to total drag in the Stoke's law range is (A) 0.5 (B) 1 (C) 1/3 (D) 2/3

Description : The ratio of wall drag to total drag in the Stoke's law range is (A) 0.5 (B) 1 (C) 1/3 (D) 2/3

Last Answer : (D) 2/3

The terminal velocity of a solid spherical particle falling through a stationary fluid mass in the Stoke's law range is proportional to the (A) Inverse of fluid viscosity (B) Square of particle size (C) Difference in the densities of the particle & fluid (D) All (A), (B) and (C)

Description : The terminal velocity of a solid spherical particle falling through a stationary fluid mass in the Stoke's law range is proportional to the (A) Inverse of fluid viscosity (B) Square of particle size (C) Difference in the densities of the particle & fluid (D) All (A), (B) and (C)

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

The terminal velocity of a particle moving through a fluid varies as dp n . The value of n is equal to __________ in Stoke's law regime. (A) 1 (B) 0.5 (C) 2 (D) 1.5

Description : The terminal velocity of a particle moving through a fluid varies as dp n . The value of n is equal to __________ in Stoke's law regime. (A) 1 (B) 0.5 (C) 2 (D) 1.5

Last Answer : (C) 2

A particle A of diameter 10 microns settles in an oil of specific gravity 0.9 and viscosity 10 poise under Stoke's law. A particle B with diameter 20microns settling in the same oil will have a settling velocity (A) Same as that of A (B) One fourth as that of A (C) Twice as that of A (D) Four times as that of A

Description : A particle A of diameter 10 microns settles in an oil of specific gravity 0.9 and viscosity 10 poise under Stoke's law. A particle B with diameter 20microns settling in the same oil will have a settling velocity (A) ... ) One fourth as that of A (C) Twice as that of A (D) Four times as that of A

Last Answer : (B) One fourth as that of A

Stoke's law does not hold good if the size of particle is smaller than (A) 0.0002 mm (B) 0.002 mm (C) 0.02 mm (D) 0.2 mm

Description : Stoke's law does not hold good if the size of particle is smaller than (A) 0.0002 mm (B) 0.002 mm (C) 0.02 mm (D) 0.2 mm

Last Answer : (A) 0.0002 mm

Why does Stoke's Law (sedimentation) not work for measuring sand-size fractions?

Description : Why does Stoke's Law (sedimentation) not work for measuring sand-size fractions?

Last Answer : Your question and details don't exactly jibe: Are you specifically asking about sand or sand-size fractions (which could be nearly anything)? Also, while sand crystals are not typically spherical, ... used up the final dregs of what he eked out Fluid Mechanics & Dynamics class back in school.

The Gauss law employs which theorem for the calculation of charge density? a) Green theorem b) Stokes theorem c) Gauss theorem d) Maxwell equation

Description : The Gauss law employs which theorem for the calculation of charge density? a) Green theorem b) Stokes theorem c) Gauss theorem d) Maxwell equation

Last Answer : c) Gauss theorem

The Ampere law is based on which theorem? a) Green’s theorem b) Gauss divergence theorem c) Stoke’s theorem d) Maxwell theorem

Description : The Ampere law is based on which theorem? a) Green’s theorem b) Gauss divergence theorem c) Stoke’s theorem d) Maxwell theorem

Last Answer : c) Stoke’s theorem

Gauss law cannot be expressed in which of the following forms? a) Differential b) Integral c) Point d) Stokes theorem

Description : Gauss law cannot be expressed in which of the following forms? a) Differential b) Integral c) Point d) Stokes theorem

Last Answer : d) Stokes theorem

Divergence theorem is based on a) Gauss law b) Stoke’s law c) Ampere law d) Lenz law

Description : Divergence theorem is based on a) Gauss law b) Stoke’s law c) Ampere law d) Lenz law

Last Answer : a) Gauss law

Stoke's law states that the velocity at which a grain settles out of suspension, the other factors remaining constant, is dependent upon (A) Shape of grain (B) Weight of grain (C) Size of grain (D) Shape, size and weight of grain

Description : Stoke's law states that the velocity at which a grain settles out of suspension, the other factors remaining constant, is dependent upon (A) Shape of grain (B) Weight of grain (C) Size of grain (D) Shape, size and weight of grain

Last Answer : Answer: Option D

A, B and C are 3 partners in a business. Their investments are respectively Rs 2000, Rs 4,000 and Rs 3,000. A gets 30% of total profit for managing the business. The remaining profit is divided among them in the ratio of their investments. At the end of the year, the profit of Ais Rs 1100 less than the sum of the profit of B and C. What amount of income will C get? A) Rs 2100.75 B) Rs 2887.5 C) Rs 2705.75 D) Rs 2546.25

Description : A, B and C are 3 partners in a business. Their investments are respectively Rs 2000, Rs 4,000 and Rs 3,000. A gets 30% of total profit for managing the business. The remaining profit is divided among them in the ratio ... of income will C get? A) Rs 2100.75 B) Rs 2887.5 C) Rs 2705.75 D) Rs 2546.25

Last Answer : Answer: B) The ratio of profit of A, B and C is 2000:4000:3000=2:4:3. Let the annual profit be P. Then, A will get 0.3p for managing the business. And, remaining 0.7p will be distributed in the ratio of their ... ⇒ 7/9 0.7p−2/9 0.7p−0.3p=1100 ⇒ p=12,375 So, C's share=3/9 0.7p=Rs 2887.5

For a turbine agitated and baffled tank, operating at low Reynold's number (based on impeller diameter), the power number (Np ) varies with NRe as (A) Np ∝ NRe (B) Np ∝ √NRe (C) Np → constan(D) Np ∝ 1/NRe

Description : For a turbine agitated and baffled tank, operating at low Reynold's number (based on impeller diameter), the power number (Np ) varies with NRe as (A) Np ∝ NRe (B) Np ∝ √NRe (C) Np → constan (D) Np ∝ 1/NRe

Last Answer : (D) Np ∝ 1/NRe

. (NSh /NRe .NSc ) is termed in mass transfer operation as the (A) Stanton number (B) Peclet number (C) Thermal diffusivity (D) Momentum diffusivity

Description : . (NSh /NRe .NSc ) is termed in mass transfer operation as the (A) Stanton number (B) Peclet number (C) Thermal diffusivity (D) Momentum diffusivity

Last Answer : (A) Stanton number

(NRe . NSc ) is termed in mass transfer operation as the __________ number. (A) Stanton (B) Sherwood (C) Peclet (D) None of these

Description : (NRe . NSc ) is termed in mass transfer operation as the __________ number. (A) Stanton (B) Sherwood (C) Peclet (D) None of these

Last Answer : (C) Peclet

NRe . NPr ) (D/L) is called the __________ number (A) Peclet (B) Stanton (C) Graetz (D) None of these

Description : NRe . NPr ) (D/L) is called the __________ number (A) Peclet (B) Stanton (C) Graetz (D) None of these

Last Answer : (C) Graetz

The Nusselt number for fully developed (both thermally and hydrodynamically) laminar flow through a circular pipe whose surface temperature remains constant is (A) 1.66(B) 88.66 (C) 3.66 (D) Dependent on NRe only

Description : The Nusselt number for fully developed (both thermally and hydrodynamically) laminar flow through a circular pipe whose surface temperature remains constant is (A) 1.66 (B) 88.66 (C) 3.66 (D) Dependent on NRe only

Last Answer : (C) 3.66

Reynold's analogy states that (A) Nst α f (B) Nst α NRe (C) NNu α f (D) NRe α f

Description : Reynold's analogy states that (A) Nst α f (B) Nst α NRe (C) NNu α f (D) NRe α f

Last Answer : (A) Nst α f

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

The Nusselt number for fully developed (both thermally and hydrodynamically) laminar flow through a circular pipe, where the wall heat flux is constant, is(A) 2.36(B) 4.36(C) 120.36(D) Dependent on NRe only

Description : The Nusselt number for fully developed (both thermally and hydrodynamically) laminar flow through a circular pipe, where the wall heat flux is constant, is (A) 2.36 (B) 4.36 (C) 120.36 (D) Dependent on NRe only

Last Answer : (B) 4.36

For the free settling of a spherical particle through a fluid, the slope of, CD-log NRe , plot is (A) 1(B) -1 (C) 0.5 (D) -0.5

Description : For the free settling of a spherical particle through a fluid, the slope of, CD-log NRe , plot is (A) 1 (B) -1 (C) 0.5 (D) -0.5

Last Answer : (B) -1

The equation f -0.5 = 4.07 loge (NRe √f) -0.6 is called the __________.(A) Colebrook formula (B) Von-Karman equation (C) Fanning equation (D) None of these

Description : The equation f -0.5 = 4.07 loge (NRe √f) -0.6 is called the __________. (A) Colebrook formula (B) Von-Karman equation (C) Fanning equation (D) None of these

Last Answer : (B) Von-Karman equation

Colebrook equation for friction factor in turbulent flow is given by, f -0.5 = -4 loge [(ε/D) + (1.26/NRe √F). It reduces to Nikuradse equation for a value of (ϵ/D) equal to (A) 0(B) 1 (C) ∞ (D) 0.5

Description : Colebrook equation for friction factor in turbulent flow is given by, f -0.5 = -4 loge [(ε/D) + (1.26/NRe √F). It reduces to Nikuradse equation for a value of (ϵ/D) equal to (A) 0 (B) 1 (C) ∞ (D) 0.5

Last Answer : (B) 1

What is the value of Fanning friction factor f ' for smooth pipe at NRe = 10 6 approximately? (A) 0.003 (B) 0.01 (C) 0.1(D) 0.3

Description : What is the value of Fanning friction factor f ' for smooth pipe at NRe = 10 6 approximately? (A) 0.003 (B) 0.01 (C) 0.1 (D) 0.3

Last Answer : (A) 0.003

In the complete turbulence zone (in rough pipes), the (A) Rough and smooth pipes have the same friction factor (B) Laminar film covers the roughness projections (C) Friction factor depends upon NRe only (D) Friction factor is independent of the relative roughness

Description : In the complete turbulence zone (in rough pipes), the (A) Rough and smooth pipes have the same friction factor (B) Laminar film covers the roughness projections (C) Friction factor depends upon NRe only (D) Friction factor is independent of the relative roughness

Last Answer : (D) Friction factor is independent of the relative roughness

The equation relating friction factor to Reynold number, f -0.5 = 4 loge (NRe /√f) -0.4 , is called the __________ equation. (A) Nikuradse (B) Von-Karman

Description : The equation relating friction factor to Reynold number, f -0.5 = 4 loge (NRe /√f) -0.4 , is called the __________ equation. (A) Nikuradse (B) Von-Karman

Last Answer : (B) Ergun's

Euler’s formula is not valid for mild steel column when slenderness ratio is (a) More than 100 (b) Less than 100 (c) Less than 80 (d)More than 80

Description : Euler’s formula is not valid for mild steel column when slenderness ratio is (a) More than 100 (b) Less than 100 (c) Less than 80 (d)More than 80

Last Answer : (c) Less than 80

The temperature at which plastic layer formation takes place during carbonisation of coal varies from __________ °C. (A) 100 to 150 (B) 350 to 450 (C) 550 to 650 (D) 700 to 850

Description : The temperature at which plastic layer formation takes place during carbonisation of coal varies from __________ °C. (A) 100 to 150 (B) 350 to 450 (C) 550 to 650 (D) 700 to 850

Last Answer : (B) 350 to 450

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Description : Optimum reaction temperature in steam reforming of naphtha is __________ °C. (A) 700 - 1000 (B) 300 - 450 (C) 1500-1700 (D) 100-200

Last Answer : (A) 700 - 1000

Beyond what concentration of H2S in air, acute danger to human life exists? (A) 50 ppm (B) 100 ppm (C) 300 ppm (D) 700 ppm

Description : Beyond what concentration of H2S in air, acute danger to human life exists? (A) 50 ppm (B) 100 ppm (C) 300 ppm (D) 700 ppm

Last Answer : (D) 700 ppm

The usual energy consumption in electric arc furnace steel making is __________ KWh/ton of steel. (A) 60 - 100 (B) 400 - 700 (C) 1200 -1500 (D) 2000 - 2300

Description : The usual energy consumption in electric arc furnace steel making is __________ KWh/ton of steel. (A) 60 - 100 (B) 400 - 700 (C) 1200 -1500 (D) 2000 - 2300

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