Description : What is the co-efficient of contraction, if a fluid jet discharging from a 50 mm diameter orifice has a 40 mm diameter at its vena-contracta? (A) 0.64 (B) 1.65 (C) 0.32 (D) 0.94
Last Answer : (A) 0.64
Description : Re-entrant or Borda's mouthpiece is an __________ mouthpiece. (A) Internal (B) External (C) Both A and B (D) None of these
Last Answer : Answer: Option A
Description : Consider the following devices : 1. Orifice 2. Borda’s mouthpiece running free 3. Bell mouthed orifice 4. External mouthpiece What is the correct sequence of these devices by decreasing magnitude of coefficient of discharge? a) 2, 3, 1 and 4 b) 4, 3, 1 and 2 c) 4, 1, 3 and 2 d) 2, 1, 3 and 4
Last Answer : b) 4, 3, 1 and 2
Description : The fluid jet discharging from a 2" diameter orifice has a diameter of 1.75" at its vena-contracta. The co-efficient of contraction is (A) 1.3 (B) 0.766 (C) 0.87 (D) None of these
Last Answer : (B) 0.766
Description : Co-efficient of discharge (Cd ) is defined as actual discharge/theoretical discharge and is equal to Cc . Cv ; where Cc = Co-efficient of contraction and Cv = co-efficient of velocity. Cd of an orifice is usually about (A) 0.42 (B) 0.62 (C) 0.82 (D) 0.98
Last Answer : (B) 0.62
Description : 05. In an internal mouthpiece, if the jet after contraction expands and fills up the whole mouthpiece, then the mouthpiece is said to be running free. A) True B) False
Last Answer : B
Last Answer : A
Description : In an internal mouthpiece, if the jet after contraction does not touch the sides of the mouthpiece, then the mouthpiece is said to be (A) Running full (B) Running free (C) Partially running full (D) Partially running free
Last Answer : Answer: Option B
Description : A coal with high ash content is undesirable, as (A) It is abrasive to the coal pulveriser (i.e. ball mill) and the combustion chamber (B) The ash in molten condition gets absorbed in the pores of the ... and stick to the boiler tubes thereby reducing the heat transfer (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : The discharge through a Venturimeter depends upon (A) Pressure drop only (B) Its orientation (C) Co-efficient of contraction only (D) None of these
Last Answer : (A) Pressure drop only
Description : Cd , Cc and Cv are related (for flow through an orifice) as (where, Cd = discharge co-efficient, Cc = co-efficient of contraction = (area of jet at venacontracta/area of opening), Cv = co-efficient of velocity = (actual velocity ... A) Cd = Cc /Cv (B) Cd = Cc .Cv (C) Cd = Cv / Cc (D) None of these
Last Answer : (B) Cd = Cc .Cv
Description : Pick out the correct statement pertaining to Venturimeter. (A) A Venturimeter with a fixed pressure drop discharges more, when the flow is vertically downward, than when the flow is vertically upward (B ... , when compressibility is taken into account, than when it is neglected (D) None of these
Last Answer : (D) None of these
Description : Bernoulli's equation for fluid flow is derived following certain assumptions. Out of the assumptions listed below, which set of assumptions is used in derivation of Bernoulli's equation? A. Fluid flow is frictionless & irrotational. B. Fluid flow is ... A, C, D (B) B, D, E (C) A, B, E (D) A, D, E
Last Answer : (C) A, B, E
Description : Pascal's law is valid, only when the fluid is (A) Frictionless and at rest (B) At rest (C) At rest and when the frictionless fluid is in motion (D) None of these
Last Answer : (B) At rest
Description : Select the wrong statement pertaining to flow of an incompressible fluid through a Venturimeter. (A) For frictionless flow, the fluid pressure entering the venturi meter will be exactly equal ... than an orificemeter (D) Venturimeter incurs less power loss compared to an equivalent orificemeter
Last Answer : (C) Venturimeter occupies less space than an orificemeter
Description : The pressure intensity is the same in all directions at a point in a fluid (A) Only when the fluid is frictionless (B) Only when the fluid is at rest having zero velocity (C) When there is ... relative to an adjacent layer (D) Regardless of the motion of one fluid layer relative to an adjacent layer
Last Answer : C) When there is no motion of one fluid layer relative to an adjacent layer
Description : In an incompressible flow of fluid, the fluid (A) Temperature remains constant (B) Compressibility is greater than zero (C) Density does not change with pressure & temperature (D) Is frictionless
Last Answer : (C) Density does not change with pressure & temperature
Description : An ideal fluid is (A) Frictionless & incompressible (B) One, which obeys Newton's law of viscosity (C) Highly viscous (D) None of these
Last Answer : (A) Frictionless & incompressible
Description : In deriving Bernoulli's equation, fluid is assumed to be (A) Incompressible, frictionless, steady, along a streamline (B) Uniform, steady, incompressible, along a streamline (C) Steady, density being pressure dependent, frictionless (D) None of these
Last Answer : (A) Incompressible, frictionless, steady, along a streamline
Description : Pascal law is not applicable for a/an __________ fluid. (A) Accelerating frictionless (B) Static (C) Uniformly moving (D) None of these
Description : The normal stress is the same in all directions at a point in a fluid, only when the fluid (A) Is at rest & has zero viscosity (B) Is frictionless (C) Fluid layer has no motion relative to an adjacent layer of fluid (D) is incompressible & frictionless
Last Answer : (D) is incompressible & frictionless
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
Description : For a laminar flow of fluid in a circular tube, 'h1 ' is the convective heat transfer co-efficient at velocity 'V1 '. If the velocity is reduced by half and assuming the fluid properties are constant, the new convective heat transfer co-efficient is (A) 1.26 h1 (B) 0.794 h1 (C) 0.574 h1 (D) 1.741 h1
Last Answer : (B) 0.794 h1
Description : Pick out the wrong statement. (A) The shear stress at the pipe (dia = D, length = L) wall in case of laminar flow of Newtonian fluids is (D/4L). ∆p (B) In the equation, T. gc = k. ... to motion (D) With increase in the Mach number >0.6, the drag co-efficient decreases in case of compressible fluids
Last Answer : (D) With increase in the Mach number >0.6, the drag co-efficient decreases in case of compressible fluids
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
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
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
Description : The normal stress is same in all directions at a point in a fluid (A) Only when the fluid is frictionless (B) Only when the fluid is incompressible and has zero viscosity (C) When there ... to an adjacent layer (D) Irrespective of the motion of one fluid layer relative to an adjacent layer
Last Answer : Answer: Option C
Description : Pick out the wrong statement. (A) Superheated steam is preferably not used for process heating because of its low heat transfer film co-efficient (B) In a shell and tube heat exchanger ... surface heat exchangers, when the direction of fluid flow is parallel to the axis of the tube
Last Answer : (C) S.I. unit of fouling factor is Watt/m2 .°K
Description : Convective heat transfer co-efficient in case of fluid flowing in tubes is not affected by the tube length/diameter ratio, if the flow is in the __________ zone. (A) Laminar (B) Transition (C) Both 'a' & 'b' (D) Highly turbulent
Last Answer : (D) Highly turbulent
Description : In an extended surface heat exchanger, fluid having lower co-efficient (A) Flows through the tube (B) Flows outside the tubes (C) Can flow either inside or outside the tubes (D) Should not be used as it gives very high pressure drop
Last Answer : (B) Flows outside the tubes
Description : Out of the following four assumptions used in the derivation of theequation for LMTD [LMTD = (∆t1 - ∆t2 )/ln(∆t1 /∆t2 )], which one is subject to the largest deviation in practice ? (A) Constant ... (B) Constant rate of fluid flow (C) Constant specific heat (D) No partial phase change in the system
Last Answer : (B) Constant rate of fluid flow
Description : The co-efficient of drag and lift for an incompressible fluid depends on the (A) Reynolds number (B) Froude number (C) Mach number (D) All (A), (B) and (C)
Last Answer : (A) Reynolds numbe
Description : Which of the following is not concerned with the fluid-particle interaction? (A) Drag co-efficient (B) Froude number (C) Galileo number (D) Weber number
Last Answer : (D) Weber number
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
Description : `C(s)+O_(2)(g)rarr CO_(2)(g)+94.0` K cal. `CO(g)+(1)/(2)O_(2)(g)rarr CO_(2)(g), Delta H=-67.7` K cal. From the above reactions find how much heat (Kca
Last Answer : `C(s)+O_(2)(g)rarr CO_(2)(g)+94.0` K cal. `CO(g)+(1)/(2)O_(2)(g)rarr CO_(2)(g), Delta H=-67.7` K cal. ... g)` A. `20.6` B. `26.3` C. `44.2` D. `161.6`
Description : The coefficient of discharge for an external mouthpiece is (A) 0.375 (B) 0.5 (C) 0.707 (D) 0.855
Last Answer : Answer: Option D
Description : The discharge through an external mouthpiece is given by (where a = Cross-sectional area of the mouthpiece, and H = Height of liquid above the mouthpiece) (A) 0.855 a. gH) (B) 1.855 aH. g) (C) 1.585 a. gH) (D) 5.85 aH. g)
Description : When an internal mouthpiece is running free, the discharge through the mouthpiece is (where a = Area of mouthpiece, and H = Height of liquid above the mouthpiece) (A) 0.5 a. gH (B) 0.707 a. gH (C) 0.855 a. gH (D) a. gH
Description : In an external mouthpiece, the absolute pressure head at vena contracta is __________ the atmospheric pressure head by an amount equal to 0.89 times the height of the liquid, above the vena contracta. (A) Less than (B) More than (C) Equal to (D) None of these
Description : A 10 kilogram mass rests on a horizontal frictionless surface. A horizontal force of 5 Newtons is applied to the mass. After the force has been applied for 1 second, the velocity of the mass is: w) 0 meters per second x) 0.5 meters per second y) 5 meters per second z) 50 meters per second
Last Answer : ANSWER: X -- 0.5 METERS PER SECOND
Description : The rough value of diffusion co-efficient of water vapor into air at 25°C may be about __________ cm2 /sec. (A) 0.25 (B) 2.5 (C) 1.25 (D) 0.0025
Last Answer : (A) 0.25
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 : A 10 cm dia steam pipe, carrying steam at 180°C, is covered with an insulation (conductivity = 0.6 W/m.°C). It losses heat to the surroundings at 30°C. Assume a heat transfer co-efficient of 0 ... that of the un-insulated steam pipe (D) Less than the steam pipe with 5 cms insulation
Last Answer : (B) Less than that of the un-insulated steam pipe
Description : The thermal efficiency of a reversible heat engine operating between two given thermal reservoirs is 0.4. The device is used either as a refrigerator or as a heat pump between the same reservoirs. Then the coefficient of performance as a ... )R = 1.5; (COP)HP = 2.5 (D) (COP)R = (COP)HP = 2.5
Last Answer : (C) (COP)R = 1.5; (COP)HP = 2.5
Description : . The inner wall of a furnace is at a temperature of 700°C. The composite wall is made of two substances, 10 and 20 cm thick with thermal conductivities of 0.05 and 0.1 W.m-1.°C-1 respectively. The ambient air is at 30°C ... from the outer surface in W.m-2 is (A) 165.4 (B) 167.5 (C) 172.5 (D) 175
Last Answer : (A) 165.4
Description : What is the value of co-efficient of discharge for square edged circular orifice (for β = 0.3 to 0.5)? (A) 0.61 - 0.63 (B) 0.5 - 0.75 (C) 0.75 - 0.90 (D) 0.35 - 0.55
Last Answer : (A) 0.61 - 0.63
Description : What is the critical radius of insulation (cms) for a metallic cylinder, if the convective heat transfer co-efficient with the ambient atmosphere is 5 W/m2. °K? Thermal conductivity of metal and insulation material are 40 and 0.1 W/m.°K respectively. (A) 2 (B) 8 (C) 10 (D) 40
Last Answer : (A) 2
Description : Co-efficient of performance of a Carnot cycle refrigerator operating between - 23°C and + 27°C is (A) 3 (B) 5 (C) 0.5 (D) 1.5
Last Answer : Option A