Heat and Mass Transfer Which of the following is the case of heat transfer by radiation? Heating of building Blast furnace Cooling of parts in furnace Heat received by a person from fireplace Heating of building Blast furnace Cooling of parts in furnace Heat received by a person from fireplace 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 Planck’s law holds good for polished bodies black bodies All of these all coloured bodies polished bodies black bodies All of these all coloured bodies ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The energy distribution of an ideal reflector at higher temperatures is largely in the range of Wavelength has nothing to do with it Shorter wavelength Remain same at all wavelengths Longer wavelength Wavelength has nothing to do with it Shorter wavelength Remain same at all wavelengths Longer wavelength ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Reynolds number is the ratio of Inertia force to viscous force Energy transferred by convection to that by conduction None of these Kinematic viscosity to thermal diffusivity Inertia force to viscous force Energy transferred by convection to that by conduction None of these Kinematic viscosity to thermal diffusivity ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Which of the following has least value of conductivity? Glass Water Plastic Air Glass Water Plastic Air ANSWER DOWNLOAD EXAMIANS APP
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