Heat and Mass Transfer The total radiation from a black body per second per unit area is ________ fourth power of the absolute temperature. This statement is known as Stefan Boltzmann law. Equal to Directly proportional to None of these Inversely proportional to Equal to Directly proportional to None of these Inversely proportional to ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A steam pipe is to be insulated by two insulating materials put over each other. For best results Both may be put in any order Better insulation should be put over pipe and better one over it Inferior 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 Both may be put in any order Better insulation should be put over pipe and better one over it Inferior 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 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer In free convection heat transfer transition from laminar to turbulent flow is governed by the critical value of the Grashoff's number Reynold's number Reynold's number, Grashoff's number Prandtl number, Grashoff's number Grashoff's number Reynold's number Reynold's number, Grashoff's number Prandtl number, Grashoff's number ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The rate of heat flow through a body is Q = [kA (T₁ - T₂)]/x. The term x/kA is known as None of these Thermal resistance Thermal coefficient Thermal conductivity None of these Thermal resistance Thermal coefficient Thermal conductivity ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The time constant of a thermocouple is The time taken to attain the final temperature to be measured The time taken to attain 63.2% of the value of initial temperature difference Determined by the time taken to reach 100°C from 0°C The time taken to attain 50% of the value of initial temperature difference The time taken to attain the final temperature to be measured The time taken to attain 63.2% of the value of initial temperature difference Determined by the time taken to reach 100°C from 0°C The time taken to attain 50% of the value of initial temperature difference ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer In convection heat transfer from hot flue gases to water tube, even though flow may be turbulent, a laminar flow region (boundary layer of film) exists close to the tube. The heat transfer through this film takes place by Both convection and conduction Convection Radiation Conduction Both convection and conduction Convection Radiation Conduction ANSWER DOWNLOAD EXAMIANS APP