Heat and Mass Transfer Depending on the radiating properties, a body will be black when (Where a = absorptivity, p = reflectivity, X = transmissivity.) X = 0, a + p = 0 P = 0, x = 0 and a = 1 P= 1, T = 0 and a = 0 P = 0, x = 1 and a = 0 X = 0, a + p = 0 P = 0, x = 0 and a = 1 P= 1, T = 0 and a = 0 P = 0, x = 1 and a = 0 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Absorptivity of a body will be equal to its emissivity When system is under thermal equilibrium At all temperatures At critical temperature At one particular temperature When system is under thermal equilibrium At all temperatures At critical temperature At one particular temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The highest thermal diffusivity is of Lead Concrete Iron Wood Lead Concrete Iron Wood ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer In regenerator type heat exchanger, heat transfer takes place by A complete separation between hot and cold fluids Direct mixing of hot and cold fluids Flow of hot and cold fluids alternately over a surface Generation of heat again and again A complete separation between hot and cold fluids Direct mixing of hot and cold fluids Flow of hot and cold fluids alternately over a surface Generation of heat again and again ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat transfer takes place according to Second law of thermodynamics Kirchhoff's law First law of thermodynamics Zeroth law of thermodynamics Second law of thermodynamics Kirchhoff's law First law of thermodynamics Zeroth law of thermodynamics ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According to Prevost theory of heat exchange It is impossible to transfer heat from low temperature source to t high temperature source Heat transfer in most of the cases takes place by combination of conduction, convection and radiation All bodies above absolute zero emit radiation Heat transfer by radiation requires no medium It is impossible to transfer heat from low temperature source to t high temperature source Heat transfer in most of the cases takes place by combination of conduction, convection and radiation All bodies above absolute zero emit radiation Heat transfer by radiation requires no medium ANSWER DOWNLOAD EXAMIANS APP