Heat and Mass Transfer Kirchhoff's law states that The wave length corresponding to the maximum energy is proportional to the absolute temperature 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 None of these 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 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 None of these The total radiation from a black body per second per unit area is directly proportional to the fourth power of the absolute temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer If the energy radiated per second per sq. cm. of the surface for wave lengths lying between λ, and λ + dλ is represented by (eλ.dλ), then eλ is called Absorptive power None of these Emissivity Emissive power Absorptive power None of these Emissivity Emissive power ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According to Newton's law of cooling, the heat transfer from a hot body to a cold body is Both (A) and (B) Directly proportional to the surface area Either (A) or (B) Directly proportional to the difference of temperatures between the two bodies Both (A) and (B) Directly proportional to the surface area Either (A) or (B) Directly proportional to the difference of temperatures between the two bodies ANSWER DOWNLOAD EXAMIANS APP
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 81 270 3 9 81 270 3 9 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer In counter current flow heat exchanger, the logarithmic temperature difference between the fluids is ________ as compared to parallel flow heat exchanger. Same None of these Greater Less Same None of these Greater Less ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of non-metallic amorphous solids with decrease in temperature Decreases Increases Remain constant May increase or decrease depending on temperature Decreases Increases Remain constant May increase or decrease depending on temperature ANSWER DOWNLOAD EXAMIANS APP
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