Heat and Mass Transfer A steam pipe is to be insulated by two insulating materials put over each other. For best results Better insulation should be put over pipe and better one over it Whether to put inferior OIL over pipe or the better one would depend on steam temperature Inferior insulation should be put over pipe and better one over it Both may be put in any order Better insulation should be put over pipe and better one over it Whether to put inferior OIL over pipe or the better one would depend on steam temperature Inferior insulation should be put over pipe and better one over it Both may be put in any order ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal diffusivity of a substance is All of these Directly proportional to the thermal conductivity Inversely proportional to specific heat Inversely proportional to density of substance All of these Directly proportional to the thermal conductivity Inversely proportional to specific heat Inversely proportional to density of substance ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer In counter flow heat exchangers Both the fluids at exit are in their hottest state Both the fluids at inlet are in their hottest state Both the fluids at inlet (of heat exchanger where hot fluid enters) are in their coldest state One fluid is in hottest state and other in coldest state at inlet Both the fluids at exit are in their hottest state Both the fluids at inlet are in their hottest state Both the fluids at inlet (of heat exchanger where hot fluid enters) are in their coldest state One fluid is in hottest state and other in coldest state at inlet ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The critical radius is the insulation radius at which the resistance to heat flow is Zero Maximum None of these Minimum Zero Maximum None of these Minimum ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The logarithmic mean temperature difference (tm) is given by (where Δt1 and Δt2 are temperature differences between the hot and cold fluids at entrance and exit) tm = loge (Δt1 - Δt2)/ Δt1/Δt2 tm = (Δt1 - Δt2)/ loge (Δt1/Δt2) tm = loge (Δt1/Δt2)/ (Δt1 - Δt2) tm = tm = (Δt1 - Δt2) loge (Δt1/Δt2) tm = loge (Δt1 - Δt2)/ Δt1/Δt2 tm = (Δt1 - Δt2)/ loge (Δt1/Δt2) tm = loge (Δt1/Δt2)/ (Δt1 - Δt2) tm = tm = (Δt1 - Δt2) loge (Δt1/Δt2) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The rate of energy emission from unit surface area through unit solid angle, along a normal to the surface, is known as Transmissivity Intensity of radiation Reflectivity Emissivity Transmissivity Intensity of radiation Reflectivity Emissivity ANSWER DOWNLOAD EXAMIANS APP
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