Heat and Mass Transfer According of Kirchhoff's law Emissive power and absorptivity are constant for all bodies 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 depends on temperature Radiant heat is proportional to fourth power of absolute temperature Emissive power and absorptivity are constant for all bodies 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 depends on temperature Radiant heat is proportional to fourth power of absolute temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Heat is transferred by all three modes of transfer, viz. conduction, convection and radiation in Refrigerator condenser coils Electric heater Steam condenser Boiler Refrigerator condenser coils Electric heater Steam condenser Boiler ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The rate of energy transferred by convection to that by conduction is called Biot number Nusselt number Peclet number Stanton number Biot number Nusselt number Peclet number Stanton number ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of water _________ with rise in temperature. May increase or decrease depending upon temperature Decreases Remain same Increases May increase or decrease depending upon temperature Decreases Remain same Increases ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Wien’s law states that the wave length corresponding to ________ is proportional to the absolute temperature. Both (A) and (B) None of these Minimum energy Maximum energy Both (A) and (B) None of these Minimum energy Maximum energy ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The critical temperature is the temperature Below which a gas is always liquefied Above which a gas may explode Above which a gas will never liquefied Below which a gas does not obey gas laws Below which a gas is always liquefied Above which a gas may explode Above which a gas will never liquefied Below which a gas does not obey gas laws ANSWER DOWNLOAD EXAMIANS APP