Heat and Mass Transfer An electric cable of aluminium conductor (k = 240 W/mK) is to be insulated with rubber (k = 0.15 W/mK). The cable is to be located in air (h = 6 W/m²). The critical thickness of insulation will be 800 mm 160 mm 40 mm 25 mm 800 mm 160 mm 40 mm 25 mm ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According to Prevost theory of heat exchange Heat transfer by radiation requires no medium Heat transfer in most of the cases takes place by combination of conduction, convection and radiation All bodies above absolute zero emit radiation It is impossible to transfer heat from low temperature source to t high temperature source Heat transfer by radiation requires no medium Heat transfer in most of the cases takes place by combination of conduction, convection and radiation All bodies above absolute zero emit radiation It is impossible to transfer heat from low temperature source to t high temperature source ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The amount of radiation mainly depends on All of these Nature of body Type of surface of body Temperature of body All of these Nature of body Type of surface of body Temperature of body ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of glass wool varies from sample to sample because of variation in Porosity All of these Composition Density Porosity All of these Composition Density ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of non-metallic amorphous solids with decrease in temperature May increase or decrease depending on temperature Decreases Remain constant Increases May increase or decrease depending on temperature Decreases Remain constant Increases ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A designer chooses the values of fluid flow rates and specific heats in such a manner that the heat capacities of the two fluids are equal. A hot fluid enters the counter flow heat exchanger at 100°C and leaves at 60°C. A cold fluid enters the heat exchanger at 40°C. The mean temperature difference between the two fluids is 60°C 66.7°C 20°C 40°C 60°C 66.7°C 20°C 40°C ANSWER DOWNLOAD EXAMIANS APP