The value of Lewis number (Le = Sc/Pr) for air-water vapour system is
around
(A) 1
(B) 0.24
Description : Lewis number (Le) isA) Sc × Pr (B) Pr × St (C) Sh × Pr (D) St × Sh
Last Answer : (A) Sc × Pr
Description : For the case of flow of air past a wet bulb thermometer (air water vapour system), the approximate value of h2 /ky .Cz is around (A) 0.60 (B) 0.24 (C) 1 (D) 0.72
Last Answer : (C) 1
Description : In forced convection, the Nusselt number is a function of (A) Re and Pr (B) Re and Gr (C) Pr and Gr (D) Re and Sc
Last Answer : (A) Re and Pr
Description : The relation, Sc = Pr = 1, is valid, when the mechanism of __________ transfer is same. (A) Heat and mass (B) Mass and momentum (C) Heat and momentum (D) Heat, momentum and mass
Last Answer : (A) Heat and mass
Description : "The rate at which a substance reacts is proportional to its active mass and the rate of a chemical reaction is proportional to the product of active masses of the reacting substances". This is the (A) Lewis- ... (B) Statement of Van't Hoff Equation (C) Le-Chatelier's principle (D) None of these
Last Answer : (D) None of these
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
Description : Did Aston Martin ever win the 24 hours of Le Mans?
Last Answer : Yes, in 1959.
Description : Schmidt number and Lewis number for pure air at atmospheric conditions are respectively (A) < 1 and ≈ 1 (B) 1 and 0 (C) > 1 and ≈ 1 (D) 0 and ≈ 1
Last Answer : (A) < 1 and ≈ 1
Description : A mixture of 10% C6H6 vapour in air at 25°C and 750 mm Hg has a dew point of 20°C. Its dew point at 30°C and 700 mm Hg will be around __________ °C. (A) 21.7 (B) 20 (C) 27.3 (D) 18.7
Last Answer : (D) 18.7
Description : For the air water system under ambient conditions, the adiabatic saturation temperature and the wet bulb temperature are nearly equal, because (A) Water has a high latent heat of evaporation (B) Lewis number is close to unity (C) They are always equal under all circumstances
Last Answer : (A) Water has a high latent heat of evaporation
Description : The Dittus-Boelter equation for convective heat transfer [(i.e. h = 0.023 (K/D) (Re) 0.8 (Pr) 0.4 ] cannot be used for (A) Low Reynold's number (B) Very low Grashoff number (C) Molten metals (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : What is there to do in (on?)/around Parris Island, SC?
Last Answer : It is close to Hilton Head with all of its attractions. You can also get some good seafood in Beaufort, a nearby city.
Description : Are there any trucking co that provides training and employment around the Myrtle Beach SC?
Last Answer : No because it is illegal to drive a truck unless you have your CDL. Try Cadets Driver Training, 826 Castlebridge Dr, Murrells Inlet, SC - (843) 651-6066
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 : Which of the following has the minimum value of COP for a given refrigeration effect? (A) Reverse Carnot cycle (B) Ordinary vapour-compression cycle (C) Vapour-compression process with a reversible expansion engine (D) Air refrigeration cycle
Last Answer : (D) Air refrigeration cycle
Description : How many dots are around the Na in the Lewis symbol for an neutral atom of Sodium?
Last Answer : Need answer
Description : At equilibrium the concentration of water in vapour phase (C* ) in kg/m3 of air space and the amount of water (m) adsorbed per kg of dry silica gel are related by, C* = 0.0667m. To maintain dry conditions in a room ... which the temperature is maintained constant) is (A) 0.0 (B) 0.2 (C) 0.4 (D) 1.0
Last Answer : (C) 0.4
Description : An air-water vapour mixture has a dry bulb temperature of 60°C and a dew point temperature of 40°C. The total pressure is 101.3 kPa and the vapour pressure of water at 40°C and 60°C are 7.30 kPa and 19.91 kPa respectively ... air is: (A) 0.048 (B) 0.079 (C) 0.122 (D) 0.152
Last Answer : (D) 0.152
Description : Peclet number (Pe) is given by (A) Pe = Re.Pr (B) Pe = Re/Pr (C) Pe = Pr /Re (D) Pe = Nu.Re
Last Answer : (A) Pe = Re.Pr
Description : If mass diffusivity in a mixture is equal to the thermal diffusivity, then the Lewis number is (A) 0 (B) 1 (C) < 1 (D) > 1
Last Answer : (B) 1
Description : "When a system in equilibrium is subjected to a change in temperature, pressure or concentration, the equilibrium is displaced in a direction which tends to undo the effect of the change." This is ... Chatelier principle (B) Kopp's rule (C) Law of corresponding state (D) Arrhenius hypothesis
Last Answer : (A) Le-Chatelier principle
Description : Le-Blanc process is a primitive process for the manufacture of (A) Caustic soda (B) Soda ash (C) Bromine from sea water (D) Hydrochloric acid
Last Answer : (B) Soda ash
Description : In the reaction, `C_(6)H_(5)NH_(2)underset(0-5^(@)C)overset(NaNO_(2)+HCl)rarr(A)underset(KCN)overset(CuCN)rarr(B)overset(H^(+)//H_(2)O)rarr(C)` the pr
Last Answer : In the reaction, `C_(6)H_(5)NH_(2)underset(0-5^(@)C)overset(NaNO_(2)+HCl)rarr(A)underset(KCN)overset(CuCN ... COOH` C. `C_(6)H_(5)OH` D. none of these
Description : At Pr > 1, conduction in an ordinary fluid flowing through a heated pipe is limited to the (A) Buffer zone (B) Turbulent core (C) Both (A) and (B) (D) Viscous sub-layer
Last Answer : (D) Viscous sub-layer
Description : In forced convection, the heat transfer depends on (A) Re, Pr (B) Re, Gr (C) Mainly Gr (D) Re only
Last Answer : (A) Re, Pr
Description : Pick out the correct equation. (A) jH = (St)(Pr) 2/3 = f/2 (B) jH = (St)(Pr) 1/3 = f/2 (C) jH = (St) 2/3 (Pr) = f/2 (D) jH = (St) 1/3 (Pr) = f/2
Last Answer : (A) jH = (St)(Pr) 2/3 = f/2
Description : The characteristic dimensionless groups for heat transfer to a fluid flowing through a pipe in laminar flow are (A) Re.Gz (B) Nu, Pr (C) Nu, Pr, Re (D) Nu, Gz
Last Answer : (D) Nu, Gz
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 : Choose the correct equation. (A) Nu = (Re) (Pr) (Gz) (B) Nu = (Re) (Pr) (St) (C) Nu = (Re) (Pr) (D) Nu = (Pr) (St)
Last Answer : (B) Nu = (Re) (Pr) (St)
Description : The rate expression for a heterogeneous catalytic reaction is given by, - rA = K.KA PA(1 + KA.PA + KR.PR), where K is surface reaction rate constant and KA and KR are absorption equilibrium constants of A and R respectively. If KR PR ... R and A) (A) E (B) E + ΔHA (C) E + ΔHA - ΔHR ) (D) ΔHA + ΔHR
Last Answer : (C) E + ΔHA - ΔHR )
Description : `" if " f(x) ={ underset( 5x" "2 le x le 3) (3x+ 4,0 le x le 2),` then `int_(0)^(3) f(x) dx=?`
Last Answer : `" if " f(x) ={ underset( 5x" "2 le x le 3) (3x+ 4,0 le x le 2),` then `int_(0)^(3) f(x) dx=?` A. `(53)/(2)` B. `(55)/(2)` C. `(57)/(2)` D.
Description : `"if "f(x) ={ underset(5x, 1,2 le x le 3)(3x+4, 0 le x le 2}},` then evaluate `int_(0)^(3) f(x) dx.`
Last Answer : `"if "f(x) ={ underset(5x, 1,2 le x le 3)(3x+4, 0 le x le 2}},` then evaluate `int_(0)^(3) f(x) dx.`
Description : No. of solutions of `16^(sin^2x)+16^(cos^2x)=10, 0 le x le 2 pi` is
Last Answer : No. of solutions of `16^(sin^2x)+16^(cos^2x)=10, 0 le x le 2 pi` is
Description : Let `cos(alpha+beta)=(4)/(5)` and let `sin(alpha-beta)=(5)/(13)`, where `0 le alpha`, `beta=(pi)/(4)`. Then`tan2alpha=`
Last Answer : Let `cos(alpha+beta)=(4)/(5)` and let `sin(alpha-beta)=(5)/(13)`, where `0 le alpha`, `beta=(pi)/(4)`. Then ... 19)/(12)` C. `(20)/(7)` D. `(25)/(16)`
Description : Solve the following inequations `(i) (sinx-2)(2sinx-1) lt 0` `(ii) (2cosx-1)(cosx) le 0` `(iii) sinx+sqrt(3)cosx ge 1` `(iv) cos^(2)x+sinx le 2` `(v)
Last Answer : Solve the following inequations `(i) (sinx-2)(2sinx-1) lt 0` `(ii) (2cosx-1)(cosx) le 0` `(iii) sinx+sqrt(3) ... ^(2)x+sinx le 2` `(v) tan^(2)x gt 3`
Description : Solve the following equation `(i) 5cos2theta+2cos^(2)"(theta)/(2)+1=0`, `-(pi)/(2) lt theta lt (pi)/(2)` `(ii) sin7theta+sin4theta+sintheta=0`, `0 le
Last Answer : Solve the following equation `(i) 5cos2theta+2cos^(2)"(theta)/(2)+1=0`, `-(pi)/(2) lt theta ... iii) tantheta+sectheta=sqrt(3)`, `0 le theta le 2pi`
Description : Solve the following inequalities `(i) |log_(3)x|-log_(3)x-3 lt 0` `(ii)(x-1)/(log_(3)(9-3^(x))-3) le 1` `(iii)log_((x-1)/(x-5))(x-2) gt 0` `(iv) log_(
Last Answer : Solve the following inequalities `(i) |log_(3)x|-log_(3)x-3 lt 0` `(ii)(x-1)/(log_(3)(9-3^(x))-3) le 1` ... gt 0` `(iv) log_(x)(x^(3)-x^(2)-2x) lt 3`
Description : Solve the following inequalities `(i) log_(5)(3x-1) lt 1` `(ii) (log_(.5)x)^(2)+log_(.5)x-2 le 0` `(iii) log_(3)(x+1)+log_(3)(x+7) ge 3` `(iv)log_(1//
Last Answer : Solve the following inequalities `(i) log_(5)(3x-1) lt 1` `(ii) (log_(.5)x)^(2)+log_(.5)x-2 le 0` `(iii) ... `(iv)log_(1//2)log_(3)(x^(2)+5)+1 le 0`
Description : Solve for `x` `(i) 2^(|x+1|)+2^(|x|)=6` and `x in I` `(ii) x^(2)+x+1+|x-3| le |x^(2)+2x-2|` `(iii) |2x-4|-2|x^(2)+x-3|+2|x-1||x+1|=0`
Last Answer : Solve for `x` `(i) 2^(|x+1|)+2^(|x|)=6` and `x in I` `(ii) x^(2)+x+1+|x-3| le |x^(2)+2x-2|` `(iii) |2x-4|-2|x^(2)+x-3|+2|x-1||x+1|=0`
Description : Vapor phase reaction of ammonia & nitric acid to produce ammonium nitrate is termed as the __________ process. (A) Haber's (B) Stengel (C) Le-chatelier's (D) Du-pont's
Last Answer : (B) Stengel
Description : If helium is introduced in a reactor containing O2 , SO2 and SO3 at equilibrium, so that total pressure increases while volume and temperature remains constant. In this case the dissociation of SO3 ( ... 's principle). (A) Decreases (B) Increases (C) Remains unaltered (D) Changes unpredictably
Last Answer : (A) Decreases
Description : Pick out the correct statement. (A) A catalyst does not change AH of the reaction (B) A catalyst changes the equilibrium point (C) Law of mass action was suggested by Le-Chatelier (D) The difference between the energy of reactants and that of the products is the activation energy
Last Answer : (A) A catalyst does not change AH of the reaction
Description : he quantitative effect of temperature on chemical equilibrium is given by the (A) Van’t-Hoff equation (B) Le-Chatelier's principle (C) Arrhenius equation (D) None of these
Last Answer : (A) Van’t-Hoff equation
Description : What is the value of a five cent coin minted in 2005 with inscription Ocean in view O The Joy E Lewis Clark 1805?
Description : When an unsaturated air-water mixture is heated at constant pressure, then (A) The partial pressure of water vapour increases (B) The specific humidity decreases (C) The relative humidity increases (D) The relative humidity decreases
Last Answer : D) The relative humidity decreases
Description : Which of the following psychrometric processes is followed by water vapour laden unsaturated air, when it is passed through solid or liquid adsorbent? (A) Cooling and dehumidification ... (C) Dehumidification with dry bulb temperature remaining constant (D) None of these
Last Answer : (B) Heating and dehumidification at almost constant wet bulb temperature
Description : Use of excess of combustion air in the combustion of fuels results in (A) Heat losses (B) Long flame (C) Condensation of water vapour from the fuel gas (D) None of these
Last Answer : (A) Heat losses
Description : When dry bulb temperature & wet bulb temperature of moist air is the same, it means that the (A) Partial pressure of water vapour is less than the total pressure (B) Humidity is < 100% & dew ... Dew point temperature of air has not reached & air is not saturated fully (D) Air is fully saturated
Last Answer : (D) Air is fully saturated
Description : 5. In "Imperial Smelting Process" for extraction of zinc, zinc vapour thus produced is quenched in the external condenser by the use of the following: (A) Jet of water at high pressure (B) Blast of air (C) Mixture of water and air (D) Rain of molten lead
Last Answer : Option D
Description : What is the atomic number of Pr ?
Last Answer : The atomic number of Pr is 59