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

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
by

1 Answer

Answer :

(B) -1
by

Related questions

For motion of spherical particles in a stationary fluid, the drag co￾efficient in hindered settling compared to that in free settling is (A) More (B) Less (C) Equal (D) More or less, depending on the type of particle

Description : For motion of spherical particles in a stationary fluid, the drag co￾efficient in hindered settling compared to that in free settling is (A) More (B) Less (C) Equal (D) More or less, depending on the type of particle

Last Answer : (A) More

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

The settling velocity of a spherical particle of diameter less than 0.1 mm as per Stock’s law, is A. Vs = 418 (Gs – Gw) d [(3T + 70)/100] B. Vs = 418 (Gs – Gw)d² [(3T + 70)/100] C. Vs = 218 (Gs – Gw)d² [(3T + 70)/100] D. Vs = 218 (Gs – Gw)d [(3T + 70)/100]

Description : The settling velocity of a spherical particle of diameter less than 0.1 mm as per Stock’s law, is A. Vs = 418 (Gs – Gw) d [(3T + 70)/100] B. Vs = 418 (Gs – Gw)d² [(3T + 70)/100] C. Vs = 218 (Gs – Gw)d² [(3T + 70)/100] D. Vs = 218 (Gs – Gw)d [(3T + 70)/100]

Last Answer : ANS: B

Following the six-tenth factor rule, if a log-log plot of capacity of the equipment vs. cost of the equipment is made, then a straight line is obtained, whose slope is equal to (A) 0.1 (B) 0.6 (C) 0.2 (D) 0.8

Description : Following the six-tenth factor rule, if a log-log plot of capacity of the equipment vs. cost of the equipment is made, then a straight line is obtained, whose slope is equal to (A) 0.1 (B) 0.6 (C) 0.2 (D) 0.8

Last Answer : (B) 0.6

Brownian movement is prominent in the particle size range of __________ microns in case of settling of a particle in a fluid. (A) 2 to 3 (B) 0.01 to 0.10 (C) 200 to 300 (D) 100 to 1000

Description : Brownian movement is prominent in the particle size range of __________ microns in case of settling of a particle in a fluid. (A) 2 to 3 (B) 0.01 to 0.10 (C) 200 to 300 (D) 100 to 1000

Last Answer : A) 2 to 3

Forces acting on a particle settling in fluid are __________ forces. (A) Gravitational & buoyant (B) Centrifugal & drag (C) Gravitational or centrifugal buoyant drag (D) External, drag & viscous

Description : Forces acting on a particle settling in fluid are __________ forces. (A) Gravitational & buoyant (B) Centrifugal & drag (C) Gravitational or centrifugal buoyant drag (D) External, drag & viscous

Last Answer : (C) Gravitational or centrifugal buoyant drag

In Newton's law range, the terminal velocity of a solid spherical particle falling through a stationary fluid mass varies as the __________ of its diameter. (A) Inverse (B) Square root (C) Second power (D) First power

Description : In Newton's law range, the terminal velocity of a solid spherical particle falling through a stationary fluid mass varies as the __________ of its diameter. (A) Inverse (B) Square root (C) Second power (D) First power

Last Answer : (B) Square root

In the Newton's law range, the terminal velocity of a solid spherical particle falling through a stationary fluid mass is __________ the fluid viscosity. (A) Directly proportional to (B) Inversely proportional to (C) Inversely proportional to the square root of (D) Independent of

Description : In the Newton's law range, the terminal velocity of a solid spherical particle falling through a stationary fluid mass is __________ the fluid viscosity. (A) Directly proportional to (B) Inversely proportional to (C) Inversely proportional to the square root of (D) Independent of

Last Answer : (B) Inversely proportional to

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)

A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle system (in SI units) is given below : Δ P/L = 375 × 10 3 VOM + 10.94 × 10 6 V2 OM (SI units) If water is to be used as the fluidising medium, the minimum fluidisation velocity, VOM is (A) 12 mm/s (B) 16 mm/s (C) 24 mm/s (D) 28 mm/s

Description : A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle ... fluidisation velocity, VOM is (A) 12 mm/s (B) 16 mm/s (C) 24 mm/s (D) 28 mm/s

Last Answer : (B) 16 mm/s

A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle system (in SI units) is given below: Δ P/L = 375 × 10 3 VOM + 10.94 × 10 6 V2 OM (SI units) If water is to be used as the fluidising medium, in actual operation, the above bed has a height = 1 m. What is the porosity of the fluidised bed? (A) 0.2 (B) 0.5 (C) 0.7 (D) 0.8

Description : A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle system ... What is the porosity of the fluidised bed? (A) 0.2 (B) 0.5 (C) 0.7 (D) 0.8

Last Answer : (C) 0.7

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

If x gram of gas is adsobed by m gram of adsorbent at pressure P the plot of log `(x)/(m)` versus log P is linear .the slope of the plot is : (n and k

Description : If x gram of gas is adsobed by m gram of adsorbent at pressure P the plot of log `(x)/(m)` versus log P is linear .the slope of the plot is : (n and k

Last Answer : If x gram of gas is adsobed by m gram of adsorbent at pressure P the plot of log `(x)/(m)` versus log P is linear ... 2 k` B. log k C. n D. `(1)/(n)`

Adsorption of a gas on a surface follows Freundlich adsorption isotherm. Plot of `"log " (x)/(m)` versus log P gives a straight line with slope equal

Description : Adsorption of a gas on a surface follows Freundlich adsorption isotherm. Plot of `"log " (x)/(m)` versus log P gives a straight line with slope equal

Last Answer : Adsorption of a gas on a surface follows Freundlich adsorption isotherm. Plot of `"log " (x ... of pressure. D. Adsorption is independent of pressure.

In Newton's law range, the drag co-efficient for the motion of spherical particle in a stationary fluid is (A) 0.44 (B) 0.044 (C) 4.4 (D) 44

Description : In Newton's law range, the drag co-efficient for the motion of spherical particle in a stationary fluid is (A) 0.44 (B) 0.044 (C) 4.4 (D) 44

Last Answer : (A) 0.44

A 30% (by volume) suspension of spherical sand particles in a viscous oil has a hindered settling velocity of 4.44 μm/s. If the Richardson Zaki hindered settling index is 4.5, then the terminal velocity of a sand grain is (A) 0.90 μm/s (B) 1 μm/s (C) 22.1 μm/s (D) 0.02 μm/s

Description : A 30% (by volume) suspension of spherical sand particles in a viscous oil has a hindered settling velocity of 4.44 μm/s. If the Richardson Zaki hindered settling index is 4.5, then the terminal velocity of a sand grain is (A) 0.90 μm/s (B) 1 μm/s (C) 22.1 μm/s (D) 0.02 μm/s

Last Answer : (B) 1 μm/s

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

A particle is settling in a liquid under Stokesian conditions. The free falling velocity of the particle is proportional to (A) √(Particle diameter) (B) Particle diameter (C) (Particle diameter)2 (D) (Particle diameter)3

Description : A particle is settling in a liquid under Stokesian conditions. The free falling velocity of the particle is proportional to (A) √(Particle diameter) (B) Particle diameter (C) (Particle diameter)2 (D) (Particle diameter)3

Last Answer : B) Particle diameter

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

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

Particle size range in which dust catcher (gravity settling chamber) works most effectively and efficiently is __________ microns. (A) < 5 (B) 10 to 25 (C) < 74 (D) > 1000

Description : Particle size range in which dust catcher (gravity settling chamber) works most effectively and efficiently is __________ microns. (A) < 5 (B) 10 to 25 (C) < 74 (D) > 1000

Last Answer : (C) < 74

If the specific gravity of a soil particle of 0.05 cm diameter is 2.67, its terminal velocity while settling in distilled water of viscosity, 0.01 poise, is (A) 0.2200 cm/sec (B) 0.2225 cm/sec (C) 0.2250 cm/sec (D) 0.2275 cm/sec

Description : If the specific gravity of a soil particle of 0.05 cm diameter is 2.67, its terminal velocity while settling in distilled water of viscosity, 0.01 poise, is (A) 0.2200 cm/sec (B) 0.2225 cm/sec (C) 0.2250 cm/sec (D) 0.2275 cm/sec

Last Answer : (D) 0.2275 cm/sec

Sorting classifiers employing differential settling methods forseparation of particles make use of the differences in their(A) Particle sizes(B) Densities(C) Terminal velocities(D) None of these

Description : Sorting classifiers employing differential settling methods forseparation of particles make use of the differences in their (A) Particle sizes (B) Densities (C) Terminal velocities (D) None of these

Last Answer : (C) Terminal velocities

For a particle settling in water at its terminal settling velocity, which of the following is true? (A) Buoyancy = weight + drag (B) Weight = buoyancy + drag (C) Drag = buoyancy + weight (D) Drag = weight

Description : For a particle settling in water at its terminal settling velocity, which of the following is true? (A) Buoyancy = weight + drag (B) Weight = buoyancy + drag (C) Drag = buoyancy + weight (D) Drag = weight

Last Answer : (B) Weight = buoyancy + drag

Value of Nusselt number [Nu = (hD/k)] for the heat transfer byconduction from a droplet or a spherical particle to a surrounding stagnant film is (A) 0.5 (B) 2 (C) 10 (D) 100

Description : Value of Nusselt number [Nu = (hD/k)] for the heat transfer byconduction from a droplet or a spherical particle to a surrounding stagnant film is (A) 0.5 (B) 2 (C) 10 (D) 100

Last Answer : (B) 2

Two particles are called to be equal settling, if they are having the same. (A) Size (B) Specific gravity (C) Terminal velocities in the same fluid & in the same field of force (D) None of these

Description : Two particles are called to be equal settling, if they are having the same. (A) Size (B) Specific gravity (C) Terminal velocities in the same fluid & in the same field of force (D) None of these

Last Answer : (C) Terminal velocities in the same fluid & in the same field of force

In classification, particles are said to be equal settling, if they have the same terminal velocities in the (A) Different fluids (B) Same fluid (C) Same field of force (D) Both (B) and (C)

Description : In classification, particles are said to be equal settling, if they have the same terminal velocities in the (A) Different fluids (B) Same fluid (C) Same field of force (D) Both (B) and (C)

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

The terminal velocity of a small sphere settling in a viscous fluid varies as the (A) First power of its diameter (B) Inverse of the fluid viscosity (C) Inverse square of the diameter (D) Square of the difference in specific weights of solid & fluid

Description : The terminal velocity of a small sphere settling in a viscous fluid varies as the (A) First power of its diameter (B) Inverse of the fluid viscosity (C) Inverse square of the diameter (D) Square of the difference in specific weights of solid & fluid

Last Answer : (B) Inverse of the fluid viscosity

. 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

The detention time (t) of a settling tank, may be defined as the time required for A. A particle to travel along its length B. A particle to travel from top surface to bottom sludge zone C. The flow of sewage to fill the tank D. None of these

Description : The detention time (t) of a settling tank, may be defined as the time required for A. A particle to travel along its length B. A particle to travel from top surface to bottom sludge zone C. The flow of sewage to fill the tank D. None of these

Last Answer : ANS: C

In a sedimentation tank (length L, width B, depth D) the settling velocity of a particle for a discharge Q, is A. Q/(B × D) B. Q/(L × D) C. Q/L D. Q/(B × L)

Description : In a sedimentation tank (length L, width B, depth D) the settling velocity of a particle for a discharge Q, is A. Q/(B × D) B. Q/(L × D) C. Q/L D. Q/(B × L)

Last Answer : ANS: D

Bode diagram is a plot of (A) log (AR) vs. log (f) and (φ) vs. log (f) (B) log (AR) vs. f and log φ vs. f (C) AR vs. log (f) and φ vs. log (f) (D) None of these

Description : Bode diagram is a plot of (A) log (AR) vs. log (f) and (φ) vs. log (f) (B) log (AR) vs. f and log φ vs. f (C) AR vs. log (f) and φ vs. log (f) (D) None of these

Last Answer : (A) log (AR) vs. log (f) and (φ) vs. log (f)

Cox chart, which is useful in the design of distillation column particularly for petroleum hydrocarbons, is a plot of (where, P = vapor pressure, T = temperature). (A) log P vs. T (B) log P vs. log T (C) T vs. P (D) P vs. log T

Description : Cox chart, which is useful in the design of distillation column particularly for petroleum hydrocarbons, is a plot of (where, P = vapor pressure, T = temperature). (A) log P vs. T (B) log P vs. log T (C) T vs. P (D) P vs. log T

Last Answer : (A) log P vs. T

The terminal velocity of a particle moving through a fluid varies as dp n . What is the value of n' for Newton's law regime? (A) 0.5 (B) 1 (C) 1.5 (D) 3

Description : The terminal velocity of a particle moving through a fluid varies as dp n . What is the value of n' for Newton's law regime? (A) 0.5 (B) 1 (C) 1.5 (D) 3

Last Answer : (A) 0.5

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

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

Gage pressure within a spherical droplet of a fluid is 'p'. What will be gage pressure within a bubble of the same size & of the same fluid? (A) p (B) 2 p (C) 0.5 p (D) 0.25 p

Description : Gage pressure within a spherical droplet of a fluid is 'p'. What will be gage pressure within a bubble of the same size & of the same fluid? (A) p (B) 2 p (C) 0.5 p (D) 0.25 p

Last Answer : (B) 2 p

Pick out the correct statement. (A) Human blood is a Newtonian fluid (B) A Newtonian fluid obeys Newton's law of cooling (C) For a non-Newtonian fluid, a straight line passes through the origin in a plot between shear stress and shear gradien

Description : Pick out the correct statement. (A) Human blood is a Newtonian fluid (B) A Newtonian fluid obeys Newton's law of cooling (C) For a non-Newtonian fluid, a straight line passes through the origin in a plot between shear stress and shear gradien

Last Answer : (B) A Newtonian fluid obeys Newton's law of cooling

From Arrhenius law, a plot of loge K versus 1/T gives a straight line with a slope of (-E/R). The unit of E/R is (A) k cal (B) k cal/°K (C) °K (D) k cal. °K

Description : From Arrhenius law, a plot of loge K versus 1/T gives a straight line with a slope of (-E/R). The unit of E/R is (A) k cal (B) k cal/°K (C) °K (D) k cal. °K

Last Answer : (C) °K

Pick out the wrong statement. (A) Visible radiation provides the necessary activation energy in photochemical reactions (B) The order and molecularity of a complex reaction may not be the same (C) For a second order reaction, the slope of the graph/plot between rate and (concentration) is equal to the rate constant (k) (D) Molecularity of the reaction is always a whole number greater than zero

Description : Pick out the wrong statement. (A) Visible radiation provides the necessary activation energy in photochemical reactions (B) The order and molecularity of a complex reaction may not be the same (C) For ... rate constant (k) (D) Molecularity of the reaction is always a whole number greater than zero

Last Answer : (B) The order and molecularity of a complex reaction may not be the same

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

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

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

Pick out the wrong statement. (A) The controlling resistance in case of heating of air by condensing steam is in the air film (B) The log mean temperature difference (LMTD) for counter flow and parallel flow can be theoretically same when any one of the fluids (hot or cold fluid) passes through the heat exchanger at constant temperature (C) In case of a 1 - 2 shell and tube heat exchanger, the LMTD correction factor value increases sharply, when a temperature cross occurs (D) Phase change in case of a pure fluid at a given pressure from liquid to vapor or vice-versa occurs at saturation temperature

Description : Pick out the wrong statement. (A) The controlling resistance in case of heating of air by condensing steam is in the air film (B) The log mean temperature difference (LMTD) for ... a pure fluid at a given pressure from liquid to vapor or vice-versa occurs at saturation temperature

Last Answer : (C) In case of a 1 - 2 shell and tube heat exchanger, the LMTD correction factor value increases sharply, when a temperature cross occurs

For a non-spherical particle, the sphericity (A) Is defined as the ratio of surface area of a sphere having the same volume as the particle to the actual surface area of the particle (B) Has the dimension of length (C) Is always less than 1 (D) Is the ratio of volume of a sphere having the same surface area as the particle to the actual volume of the particle

Description : For a non-spherical particle, the sphericity (A) Is defined as the ratio of surface area of a sphere having the same volume as the particle to the actual surface area of the particle (B) Has ... of volume of a sphere having the same surface area as the particle to the actual volume of the particle

Last Answer : (A) Is defined as the ratio of surface area of a sphere having the same volume as the particle to the actual surface area of the particle

If dp is the equivalent diameter of a non-spherical particle, Vp its volume and sp its surface area, then its sphericity is φs is defined by (A) φs = 6 Vp /dpsp (B) φs = Vp /dpsp (C) φs = 6 dpSp /Vp (D) φs = dpSp /Vp

Description : If dp is the equivalent diameter of a non-spherical particle, Vp its volume and sp its surface area, then its sphericity is φs is defined by (A) φs = 6 Vp /dpsp (B) φs = Vp /dpsp (C) φs = 6 dpSp /Vp (D) φs = dpSp /Vp

Last Answer : (A) φs = 6 Vp /dpsp

Sphericity is the ratio of the surface area of a spherical particle having the same volume as the particle to the surface area of the particle. Which of the following has the maximum value of sphericity? (A) Sphere(B) Cube(C) Cylinder (L/D = 1)(D) Raschig rings

Description : Sphericity is the ratio of the surface area of a spherical particle having the same volume as the particle to the surface area of the particle. Which of the following has the maximum value of sphericity? (A) Sphere (B) Cube (C) Cylinder (L/D = 1) (D) Raschig rings

Last Answer : (A) Sphere

The specific surface of spherical particles is given by (where D and ρ are diameter and density of particle). (A) 6/D.ρ(B) 2/D.ρ (C) 4/D.ρ (D) 12/D.ρ

Description : The specific surface of spherical particles is given by (where D and ρ are diameter and density of particle). (A) 6/D.ρ (B) 2/D.ρ (C) 4/D.ρ (D) 12/D.ρ

Last Answer : (A) 6/D.ρ

Sphericity for a non-spherical particle is given by (where, V and S are volume and surface area respectively of one particle. and, D = equivalent diameter of particle). (A) 6.V/D.S(B) V/6D.S (C) D.S/V (D) V/D.S

Description : Sphericity for a non-spherical particle is given by (where, V and S are volume and surface area respectively of one particle. and, D = equivalent diameter of particle). (A) 6.V/D.S (B) V/6D.S (C) D.S/V (D) V/D.S

Last Answer : (B) V/6D.S (C) D.S/V (D) V/D.S