Heat and Mass Transfer Thermal conductivity of solid metals with rise in temperature normally Increases Decreases May increase or decrease depending on temperature Remain constant Increases Decreases May increase or decrease depending on temperature Remain constant ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer When heat is transferred from hot body to cold body, in a straight line, without affecting the intervening medium, it is referred as heat transfer by Radiation Conduction Convection Conduction and convection Radiation Conduction Convection Conduction and convection ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of wood depends on Temperature Density Moisture All of these Temperature Density Moisture All of these ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Wien’s law states that the wave length corresponding to ________ is proportional to the absolute temperature. Minimum energy Maximum energy None of these Both (A) and (B) Minimum energy Maximum energy None of these Both (A) and (B) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat transfer by conduction through a thick cylinder (Q) is given by (where T₁ = Higher temperature, T₂ = Lower temperature, r₁ = Inside radius, r₂ = Outside radius, l = Length of cylinder, and k = Thermal conductivity) Q = [2πlk (T₁ - T₂)]/2.3 log (r₂/r₁) Q = 2.3 log (r₂/r₁)/[2πlk (T₁ - T₂)] Q = [2π (T₁ - T₂)]/2.3 lk log (r₂/r₁) Q = = 2πlk/2.3 (T₁ - T₂) log (r₂/r₁) Q = [2πlk (T₁ - T₂)]/2.3 log (r₂/r₁) Q = 2.3 log (r₂/r₁)/[2πlk (T₁ - T₂)] Q = [2π (T₁ - T₂)]/2.3 lk log (r₂/r₁) Q = = 2πlk/2.3 (T₁ - T₂) log (r₂/r₁) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Cork is a good insulator because it has Atoms colliding frequency Porous body Free electrons Low density Atoms colliding frequency Porous body Free electrons Low density ANSWER DOWNLOAD EXAMIANS APP
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