MCQ: HEAT TRANSFER-2        Dimensionless num HT        HT Symbols-2         HT Symbols-1          MCQ HT-1            PTU HT Paper Sol B             PTU HT Paper Sol A            Fin HT


Mcq on heat transfer helps in clear and deep understanding. Thus more mcq should be learnt to further increase of knowledge of heat transfer.

  1. Which Law gives the monochromatic emissive power?

(a) Stefan’s Boltzmann Law

(b) Kirchhoff’s Law

(c) Wien’s Displacement Law

(d) None

ANS: (d)

  1. All types of radiations are emitted from a body at

(a) Room temperature

(b) Boiling temperature of water

(c) Melting temperature of steel

(d) None

ANS: (d)

  1. Radiations are more harmful with

(a) Large wavelengths

(b) Short wavelengths

(c) Large as well as short wavelengths

(d) None

ANS: (b)

  1. The shape factor F12 in radiation is the ratio of

(a) Radiations falling on body 1 from body 2 to the radiations emitted from body 1

(b) Radiations falling on body 1 from body 1 to radiations emitted from body 2

(c) Radiations falling on body 2 from body 1 to radiations emitted from body 1

(d) None

ANS: (c)

  1. Shape factor is zero for a

(a) Concave body

(b) Convex body

(c) Concave as well as convex body

(d) None

  1. Shape factor depends on the

(a) Shape only

(b) Shape and size of the bodies

(c) Shape, size and orientation of the bodies

(d) None


  1. Radiation exchange between two grey bodies is given by

(a) (Eg1 – Eg2)/[(1-ϵ1)/ϵ1 A1) + 1/A1 F12 + (1-ϵ2)/ϵ2 A2)]

(b) (Eb1 – Eb2)/[(1-ϵ1)/ϵ1 A1) + 1/A1 F12 + (1-ϵ2)/ϵ2 A2)]

(c) (Eg1 – Eg2)/[(1/ϵ1 + + 1/ϵ2 –1]

(d) None

ANS: (b)

  1. Critical Reynolds number for forced convection over a flat plate is equal to

(a) 1 lac

(b) 3 lacs

(c) 5 Lacs


  1. Flow is laminar in free convection if the product of Gr.Pr is

(a) ≥109

(b) ≥108

(c) ≤108

(d) None

  1. Value of Reynolds number for a turbulent flow in a pipe is

(a) 2100

(b) 10000

(c) 5 Lacs

(d) None

ANS: (d)

  1. Reynolds number is the ratio of the

(a) Viscous force/ Inertia force

(b)Viscous force/Gravitational force

(c) Inertia force/ viscous force

(d) None


  1. Prandtl Number is given by the relation

(a) ρ Cp

(b) μ/ρ Cp

(c) k/ρ Cp

(d) None

ANS: (d)

  1. Critical heat flux is there when excess temperature is

(a) 50C

(b) 100C

(c) 300C

(d) None

ANS: (c)

  1. Boiling is a process of converting liquid into vapor

(a) On cooling alone

(b) On heating alone

(c) On heating as well as on cooling

(d) None

ANS: (b)

  1. Free convection is due to

(a) Inertia force

(b) Viscous force

(c) Buoyancy force

(d) None

ANS: (c)

  1. Free convection is

(a) visible

(b) Invisible

(c) Neither visible nor invisible

(d) None

ANS: (a)

  1. Surface resistance for a black body is

(a) Twice of a same size grey body

(b) Same as for a same size grey body

(c) Zero

(d) None

  1. Space resistance depends on

(a) Distance between the two bodies

(b) Orientation of the two bodies with respect to each other

(c) On the shape factor

(d) None

  1. The wavelength at the peak value of monochromatic emissive power

(a) Increases with the increase of temperature

(b) Decreases with the decrease of temperature

(c) Increases with the decrease of temperature

(d) None

ANS: (c)

  1. Convective heat transfer coefficient in forced convection depends upon

(a) Grashoff’s and Reynolds numbers

(b) Grashoff’s and Prandtl numbers

(c) Prandtl and Reynolds numbers

(d) None