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 Absolute temperature Cube of the absolute temperature Square of the absolute temperature Fourth power of the absolute temperature Absolute temperature Cube of the absolute temperature Square of the absolute temperature Fourth power of the absolute temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Unit of thermal conductivity in M.K.S. units is K cal/hr m² °C K cal/kg m² °C K cal m/hr m² °C K calm/hr °C K cal/hr m² °C K cal/kg m² °C K cal m/hr m² °C K calm/hr °C ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The ratio of the thickness of thermal boundary layer to the thickness of hydrodynamic boundary layer is equal to (Prandtl number) n, where n is equal to =-1/3 =-2/3 -1 1 =-1/3 =-2/3 -1 1 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Depending on the radiating properties, a body will be black when (Where a = absorptivity, p = reflectivity, X = transmissivity.) P = 0, x = 1 and a = 0 X = 0, a + p = 0 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 = 0 P = 0, x = 0 and a = 1 P= 1, T = 0 and a = 0 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Metals are good conductors of heat because 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 They contain free electrons They have high density 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) (dT/dx) (dx/dT) k. (dx/dT) k. (dT/dx) k. k. (dT/dx) (dx/dT) k. (dx/dT) k. (dT/dx) k. k. ANSWER DOWNLOAD EXAMIANS APP