Heat and Mass Transfer According to Stefan Boltzmann law, the total radiation from a black body per second per unit area is directly proportional to the Fourth power of the absolute temperature Cube of the absolute temperature Absolute temperature Square of the absolute temperature Fourth power of the absolute temperature Cube of the absolute temperature Absolute temperature Square of the absolute temperature 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 Upto the critical radius of insulation, Heat flux will decrease Added insulation will decrease heat loss Convective heat loss will be less than conductive heat loss Added insulation will increase heat loss Heat flux will decrease Added insulation will decrease heat loss Convective heat loss will be less than conductive heat loss Added insulation will increase heat loss ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Fourier's law of heat conduction is (where Q = Amount of heat flow through the body in unit time, A = Surface area of heat flow, taken at right angles to the direction of heat flow, dT = Temperature difference on the two faces of the body, dx = Thickness of the body, through which the heat flows, taken along the direction of heat flow, and k = Thermal conductivity of the body) k. k. k. (dT/dx) (dT/dx) (dx/dT) k. (dx/dT) k. k. k. (dT/dx) (dT/dx) (dx/dT) k. (dx/dT) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal diffusivity of a substance is Directly proportional to the thermal conductivity Inversely proportional to density of substance All of these Inversely proportional to specific heat Directly proportional to the thermal conductivity Inversely proportional to density of substance All of these Inversely proportional to specific heat 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 = 0, x = 0 and a = 1 P=1, T = 0 and a = 0 P = 0, x = 1 and a = 0 X = 0, a + p = 1 P = 0, x = 0 and a = 1 P=1, T = 0 and a = 0 P = 0, x = 1 and a = 0 X = 0, a + p = 1 ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS