Heat and Mass Transfer Thermal conductivity of non-metallic amorphous solids with decrease in temperature May increase or decrease depending on temperature Increases Remain constant Decreases May increase or decrease depending on temperature Increases Remain constant Decreases ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Wien’s law states that the wave length corresponding to ________ is proportional to the absolute temperature. Both (A) and (B) Maximum energy None of these Minimum energy Both (A) and (B) Maximum energy None of these Minimum energy ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal diffusivity of a substance is given by (where h = Thermal diffusivity, ρ = Density of substance, S = Specific heat, and k = Thermal conductivity) h = S/ρk h = ρS/k h = k/ ρS h = kρ/S h = S/ρk h = ρS/k h = k/ ρS h = kρ/S ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Fourier's law of heat conduction is valid for One dimensional cases only Two dimensional cases only Three dimensional cases only Regular surfaces having non-uniform temperature gradients One dimensional cases only Two dimensional cases only Three dimensional cases only Regular surfaces having non-uniform temperature gradients ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A steam pipe is to be lined with two layers of insulating materials of different thermal conductivities. For the minimum heat transfer, The better insulation must be put outside One could place either insulation on either side The better insulation must be put inside One should take into account the steam temperature before deciding as to which insulation is put where The better insulation must be put outside One could place either insulation on either side The better insulation must be put inside One should take into account the steam temperature before deciding as to which insulation is put where ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat transfer by conduction through a thick sphere is given by Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) ANSWER DOWNLOAD EXAMIANS APP
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