Heat and Mass Transfer 40% of incident radiant energy on the surface of a thermally transparent body is reflected back. If the transmissivity of the body be 0.15, then the emissivity of surface is 0.75 0.45 0.4 0.55 0.75 0.45 0.4 0.55 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The radiation emitted by a black body is known as Total radiation Full radiation Black radiation All of these Total radiation Full radiation Black radiation All of these ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Depending on the radiating properties, a body will be white when(Where a = absorptivity, p = reflectivity, x = transmissivity) P=1, T = 0 and a = 0 X = 0, a + p = 1 P = 0, x = 0 and a = 1 P = 0, x = 1 and a = 0 P=1, T = 0 and a = 0 X = 0, a + p = 1 P = 0, x = 0 and a = 1 P = 0, x = 1 and a = 0 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The total emissivity power is .defined as the total amount of radiation emitted by a black body per unit Temperature Thickness Time Area Temperature Thickness Time Area ANSWER DOWNLOAD EXAMIANS APP
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 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 Wien's law Planck's law Stefan's law Kirchhoff's law Wien's law Planck's law Stefan's law Kirchhoff's law ANSWER DOWNLOAD EXAMIANS APP