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 3 9 270 81 3 9 270 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Depending on the radiating properties, body will be transparent when(Where a = absorptivity, p = reflectivity, x = transmissivity) P = 0, x = 0 and a = 1 X = 0, a + p = 1 P=1, x = 0, and a = 0 P = 0, x= 1, and a = 0 P = 0, x = 0 and a = 1 X = 0, a + p = 1 P=1, x = 0, and a = 0 P = 0, x= 1, and a = 0 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Moisture would find its way into insulation by vapour pressure unless it is prevented by High thickness of insulation Less thermal conductivity insulator High vapour pressure A vapour seal High thickness of insulation Less thermal conductivity insulator High vapour pressure A vapour seal ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer 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. This statement is known as Stefan's law Wien's law Kirchhoff's law Planck's law Stefan's law Wien's law Kirchhoff's law Planck's law ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A designer chooses the values of fluid flow rates and specific heats in such a manner that the heat capacities of the two fluids are equal. A hot fluid enters the counter flow heat exchanger at 100°C and leaves at 60°C. A cold fluid enters the heat exchanger at 40°C. The mean temperature difference between the two fluids is 20°C 60°C 40°C 66.7°C 20°C 60°C 40°C 66.7°C ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The emissivity for a black body is 0.75 1 0.5 0.75 1 0.5 ANSWER DOWNLOAD EXAMIANS APP