Lewis number, which is important in problems involving simultaneous heat and mass transfer, is the ratio of (A) Mass diffusivity to momentum diffusivity (B) Thermal diffusivity to mass diffusivity (C) Momentum diffusivity to thermal diffusivity (D) None of these

Lewis number, which is important in problems involving simultaneous
heat and mass transfer, is the ratio of
(A) Mass diffusivity to momentum diffusivity
(B) Thermal diffusivity to mass diffusivity
(C) Momentum diffusivity to thermal diffusivity
(D) None of these
by

1 Answer

Answer :

(B) Thermal diffusivity to mass diffusivity
by

Related questions

Which of the following plays an important role in problems of simultaneous heat and mass transfer?(A) Lewis number (B) Schmidt number (C) Prandtl number (D) Sherwood number

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Last Answer : (A) Lewis number

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 than 1Nm3 of humid air (C) The Lewis number of a mixture is unity, when the thermal diffusivity is equal to the mass diffusivity

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Last Answer : (B) 1 Nm3 of dry air is lighter than 1Nm3 of humid air

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

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The Schmidt number which is defined as, μ/ρ D, is the ratio of the (A) Momentum diffusivity to the mass diffusivity (B) Thermal diffusivity to the mass diffusivity (C) Momentum diffusivity to the thermal diffusivity (D) None of these

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Prandtl number is the ratio of (A) Mass diffusivity to thermal diffusivity (B) Momentum diffusivity to thermal diffusivity (C) Thermal diffusivity to mass diffusivity (D) Thermal diffusivity to momentum diffusivity

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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

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In physical terms, Schmidt number means (A) Thermal diffusivity/mass diffusivity(B) Thermal diffusivity/momentum diffusivity(C) Momentum diffusivity/mass diffusivity(D) Mass diffusivity/thermal diffusivity

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The ratio of momentum diffusivity to thermal diffusivity is the __________ number. (A) Prandtl (B) Nusselt (C) Stanton (D) Grashoff

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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

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Heat transfer rate per unit area is called (A) Thermal conductivity (B) Heat flux (C) Heat transfer co-efficient (D) Thermal diffusivity

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