Heat and Mass Transfer Radiation is the process of heat transfer in which heat flows from a ________, in a straight line, without affecting the intervening medium. Hot body to cold body Smaller body to larger body Cold body to hot body Larger body to smaller body Hot body to cold body Smaller body to larger body Cold body to hot body Larger body to smaller body ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat transfer from a hot body to a cold body is directly proportional to the surface area and difference of temperatures between the two bodies. This statement is called Stefan's law Newton's law of cooling First law of thermodynamics Newton's law of heating Stefan's law Newton's law of cooling First law of thermodynamics Newton's law of heating ANSWER DOWNLOAD EXAMIANS APP
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 25 mm 160 mm 800 mm 40 mm 25 mm 160 mm 800 mm 40 mm ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According of Kirchhoff's law Emissive power depends on temperature Ratio of emissive power to absorptive power for all bodies is same and is equal to the emissive power of a perfectly black body Emissive power and absorptivity are constant for all bodies Radiant heat is proportional to fourth power of absolute temperature Emissive power depends on temperature Ratio of emissive power to absorptive power for all bodies is same and is equal to the emissive power of a perfectly black body Emissive power and absorptivity are constant for all bodies Radiant heat is proportional to fourth power of absolute temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The critical radius is the insulation radius at which the resistance to heat flow is Zero Minimum None of these Maximum Zero Minimum None of these Maximum ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Heat transfer in liquid and gases takes place by Convection Conduction Radiation Conduction and convection Convection Conduction Radiation Conduction and convection ANSWER DOWNLOAD EXAMIANS APP