Heat and Mass Transfer If the temperature of a solid surface changes form 27°C to 627°C, then its emissive power changes in the ratio of 270 81 9 3 270 81 9 3 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Kirchhoff's law states that The total radiation from a black body per second per unit area is directly proportional to the fourth power of the absolute temperature The wave length corresponding to the maximum energy is proportional to the absolute temperature None of these The ratio of the emissive power and absorptive power of all bodies is the same and is equal to the emissive power of a perfectly black body The total radiation from a black body per second per unit area is directly proportional to the fourth power of the absolute temperature The wave length corresponding to the maximum energy is proportional to the absolute temperature None of these The ratio of the emissive power and absorptive power of all bodies is the same and is equal to the emissive power of a perfectly black body ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Metals are good conductors of heat because They contain free electrons They have high density Their atoms collide frequently Their atoms are relatively far apart They contain free electrons They have high density Their atoms collide frequently Their atoms are relatively far apart ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of water at 20°C is of the order of 0.1 0.51 0.23 0.42 0.1 0.51 0.23 0.42 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of air at room temperature in kcal/m hr °C is of the order of 0.01 0.002 0.02 0.1 0.01 0.002 0.02 0.1 ANSWER DOWNLOAD EXAMIANS APP