According to Chilton-Colburn analogy for mass transfer, NSt
.NSc
2/3
is
equal to
(A) f
(B) f/2
(C) 2f
(D) 1/f
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
Description : The equation, (NSt × N2/3 Pr ) = f/2, is the __________ analogy. (A) Colburn (B) Reynolds (C) Prandtl (D) None of these
Last Answer : (A) Colburn
Description : The equation, Nst = f/2, is the __________ analogy. (A) Colburn (B) Reynolds (C) Prandtl (D) None o
Last Answer : (B) Reynolds
Description : JD factor for mass transfer is a function of Reynolds number. Mass transfer by molecular diffusion from a single drop to surrounding still air is given by (A) Nsh = 2 (B) Nst = 2 (C) Nsc = 2 (D) None of these
Last Answer : (A) Nsh = 2
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
Description : According to Reynolds analogy, Stanton number is equal to (where, f = Fanning friction factor) (A) 2f (B) f (C) f/2 (D) f/4
Last Answer : (C) f/2
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
Description : Colburn analogy is applicable for the value of Prandtl number from (A) 0.001 to 1 (B) 0.6 to 120 (C) 0.5 to 5 (D) 120 to 400
Last Answer : (B) 0.6 to 120
Description : Pick out the wrong statement. (A) The Reynolds analogy for mass transfer is given by Lewis relation and is applicable, when Schmidt number is one (B) Sherwood number for flow in pipes can be expressed ... flux of a component A in binary mixture of A and B is given by - Dab'.dCA/dz
Last Answer : (C) According to film theory for equimolar counter diffusion, the mass transfer coefficient is given by DAB(B)P - 3, Q - 2
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
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
Description : Analogy between mass and heat transfer is not applicable in case of (A) Same velocity profile or equal eddy diffusivities (B) Thermal or pressure mass diffusion (C) Viscous heating or chemical reaction (D) Both (B) and (C)
Last Answer : (D) Both (B) and (C)
Description : Reduction in vibration amplitude after one complete cycle of single degree free vibration with dry friction damping is_____, if where F"= frictional force between mass and surface and k =stiffness of the system. a)4F/k a b) 2f/K C) 3F/k D)8F/k
Last Answer : a)4F/k
Description : A concave mirror produces a real, inverted image of the same size of the object. Then, the object is at a distance (a) Less than f from the mirror (b) Equal to f from the mirror (c) Equal to 2f from the mirror (d) Larger than 2F from the mirror where f is the focal length of the mirror
Last Answer : Ans:(c)
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
Description : Encyclopaedia of Chemical Technology" has been (A) Authored by Kirk Othmer (B) Edited by Perry and Chilton (C) Edited by Kirk Othmer (D) Authored by Perry and Chilton
Last Answer : (C) Edited by Kirk Othmer
Description : Pick out the wrong statement pertaining to the analogy between equations of heat and mass transfer operations. (A) Sherwood number in mass transfer is analogous to Nusselt number in heat transfer ... heat transfer (D) Reynolds number remains the same in both heat and mass transfer
Last Answer : (C) Reynolds number in mass transfer is analogous to Grashoff number in heat transfer
Description : Pick out the wrong statement. (A) Mechanical agitation is required, if the system has low interfacial tension (B) Sieve tray towers are generally used for systems having low ... Prandtl analogy for heat and mass transfer considers the transfer through both laminar and turbulent layers
Last Answer : (A) Mechanical agitation is required, if the system has low interfacial tension
Description : Draw the ray diagram in each case to show the position and nature of the image formed when the object is placed: (i) at the centre of curvature of a concave mirror (ii) between the pole P and focus F of ... front of a convex mirror (iv) at 2F of a convex lens (v) in front of a concave lens -Physics
Last Answer : Answer. Nature of image: Real, inverted and same size image is formed at the centre of curvature. Nature of image: Virtual, enlarged and erect image is formed behind the mirror. Nature of image: Virtual ... : Virtual, erect and diminished image is formed between O and F on the same side of object.
Description : If `f(x) = x^(2) - 5x -36` and `g(x) = x^(2) + 9x + 20,` then for what values of `x` is `2f(x) = 3g(x)` ?
Last Answer : If `f(x) = x^(2) - 5x -36` and `g(x) = x^(2) + 9x + 20,` then for what values of `x` is `2f(x) = 3g(x)` ?
Description : Two bodies kept at a certain distance feel a gravitational force F to each other. If the distance between them is made double the former distance, the force will be - (1) 2F (2) F/2 (3) 4F (4) F/4
Last Answer : (4) F/4
Description : In coulomb damping, the amplitude of motion in each cycle is reduced by A. F/K B. 2F/K C. 4F/K D. F/4K
Last Answer : C. 4F/K
Description : An object is placed beyond 2F, in front of a convex lens, image will be formed : (a) between F and 2F (b) at focus (c) at the centre of curvature (d) between focus and Optical centre
Last Answer : (a) between F and 2F
Description : A concave lens can form a real and inverted image, when : (a) Object is placed at 2f (b) Object is placed beyond 2f (c) Object is placed between f and 2f (d) It can never form a real and
Last Answer : (d) It can never form a real and inverted image.
Description : If d is the diameter of the pipe, p is the total internal pressure, f is the permissible tensile stress and n is the effective of the joint, the thickness t of metal pipe, is (A) n (pd/2f) (B) (1/n) (pd/2f) (C) (1/n) (pd/3f) (D) (1/n) (pf/d
Last Answer : (B) (1/n) (pd/2f)
Description : The maximum magnitude of shear stress due to shear force F on a rectangular section of area A at the neutral axis, is (A) F/A (B) F/2A (C) 3F/2A (D) 2F/3A
Last Answer : (C) 3F/2A
Description : When object is placed _______ in front of convex lens than image formed is virtual, erect, magnified and on same side beyond F . a) between optical centre and F b)At F c)between F and 2F d)2F
Last Answer : a) between optical centre and F
Description : In case of convex lens when the image formed is real, inverted and same size as the object then the object should have been at ______ position of lens. a) infinity b)focus c)2F d)between F and 2F
Last Answer : c)2F
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
Description : Reynold's analogy states that (where, St = Stanton number f = friction factor) (A) St = f/2 (B) St = f/4 (C) St = 4f (D) St = f 1/2
Last Answer : (A) St = f/2
Description : All analogy equations connecting friction factor and heat transfer coefficient apply only to (A) Wall or skin friction (B) Form friction (C) Both (A) and (B) (D) Turbulent flow
Last Answer : (A) Wall or skin friction
Description : NSc /NPr is called the (A) Psychrometric ratio (B) Lewis number (C) Sherwood number (D) Stanton number
Last Answer : (B) Lewis number
Description : Mass transfer co-efficient (K) and diffusivity (D) are related according to film theory as (A) K ∝ D (B) K ∝√D (C) K ∝ D1.5 (D) K ∝ D
Last Answer : (A) K ∝ D
Description : Mass transfer co-efficient is directly proportional to DAB 0.5 , according to __________ theory. (A) Penetration (B) Surface renewal (C) Film (D) None of these
Last Answer : (A) Penetration
Description : According to the film theory of mass transfer, the mass transfer coefficient is proportional to (where, D = molecular diffusivity). (A) D (B) D2 (C) D0.5 (D) 1/D
Last Answer : (A) D
Description : Mass transfer co-efficient 'K' according to penetration theory varies with mass diffusivity as (A) D0.5 (B) D (C) 1/D (D) D1.5
Last Answer : (A) D0.5
Description : Mass transfer co-efficient is directly proportional to DAB according to the __________ theory. (A) Film (B) Penetration (C) Surface-renewal (D) None of these
Last Answer : (A) Film
Description : Pick out the wrong statement. (A) In a first order reaction, A → products; the reaction becomes slower as it proceeds, because the concentration of A decreases and the rate is proportional to the concentration ... irreversible reaction, A + B → 2C is k.CA .CB , then the reaction is always elementary
Last Answer : (C) According to the penetration theory, the mass transfer co-efficient decreases, if the exposure time of an eddy to the solute decreases
Description : In the figure shown `C_(1)=1F, C_(2)=2F and L=5H`. Initially `C_(1)` is charged 50V and `C_(2)` to 10V. Switch S is closed at time t=D. Suppose at som
Last Answer : In the figure shown `C_(1)=1F, C_(2)=2F and L=5H`. Initially `C_(1)` is charged 50V and `C_(2)` to 10V. ... will A. 10 J B. 15 J C. 25 J D. 40 J
Last Answer : In the figure shown `C_(1)=1F, C_(2)=2F and L=5H`. Initially `C_(1)` is charged 50V and `C_(2)` to 10V. ... (2) A` C. `20sqrt(3) A` D. `12sqrt(6) A`
Last Answer : In the figure shown `C_(1)=1F, C_(2)=2F and L=5H`. Initially `C_(1)` is charged 50V and `C_(2)` to 10V. ... ` B. `15sqrt(2) A` C. `10 A` D. `20 A`
Description : -3g+2f+g-4f?
Last Answer : -3g+2f+
Description : Find the total capacitances when two capacitors 2F and 5F are in series. a) 5/7 b) 12/7 c) 2/5 d) 10/7
Last Answer : d) 10/7
Description : Two condensers of capacity 2F and 3F are connected in Series and a third condenser of 1F is connected in parallel to them. The resultant capacity will
Last Answer : Two condensers of capacity 2F and 3F are connected in Series and a third condenser of 1F is connected in parallel to them. The resultant capacity will 11/5 F
Description : Mass, in force-voltage analogy, is analogous to?
Last Answer : Mass, in force-voltage analogy, is analogous to the inductance.
Description : What is the full form of 'NSC' ? -How To ?
Last Answer : The full form of 'NSC' is National Savings Certificate
Description : What is the full form of NSC ?
Last Answer : NSC 's full National Savings Certificate.
Last Answer : NSC - National Security Council / National Savings Certificate
Description : National Seed Corporation (NSC) was registered in
Last Answer : Ans. 1963
Description : The seeds produced by NSC
Last Answer : Ans. Foundation seed