Heat and Mass Transfer The value of the wave length for maximum emissive power is given by Stefan’s law Planck’s law Wine’s law Kirchhoff’s law Stefan’s law Planck’s law Wine’s law Kirchhoff’s law ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Cork is a good insulator because it has Atoms colliding frequency Porous body Low density Free electrons Atoms colliding frequency Porous body Low density Free electrons ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According to Kirchoff's law, the ratio of emissive power to absorptivity for all bodies is equal to the emissive power of a Grey body Black body Red hot body Brilliant white polished body Grey body Black body Red hot body Brilliant white polished body ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According of Kirchhoff's law Emissive power depends on temperature Emissive power and absorptivity are constant for all bodies Radiant heat is proportional to fourth power of absolute 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 depends on temperature Emissive power and absorptivity are constant for all bodies Radiant heat is proportional to fourth power of absolute 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 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Fouling factor is used None of these In heat exchanger design as a safety factor When a liquid exchanges heat with a gas In case of Newtonian fluids None of these In heat exchanger design as a safety factor When a liquid exchanges heat with a gas In case of Newtonian fluids ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat transfer by conduction through a thick sphere is given by Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) ANSWER DOWNLOAD EXAMIANS APP