Heat and Mass Transfer According of Kirchhoff's law Radiant heat is proportional to fourth power of absolute temperature Emissive power and absorptivity are constant for all bodies Ratio of emissive power to absorptive power for all bodies is same and is equal to the emissive power of a perfectly black body Emissive power depends on temperature Radiant heat is proportional to fourth power of absolute temperature Emissive power and absorptivity are constant for all bodies Ratio of emissive power to absorptive power for all bodies is same and is equal to the emissive power of a perfectly black body Emissive power depends on temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Reynolds number (RN) is given by (where h = Film coefficient, l = Linear dimension, V = Velocity of fluid, k = Thermal conductivity, t = Temperature, ρ = Density of fluid, cp = Specific heat at constant pressure, and μ = Coefficient of absolute viscosity) RN = ρ V l /μ RN = hl/k RN = μ cp/k RN = V²/t.cp RN = ρ V l /μ RN = hl/k RN = μ cp/k RN = V²/t.cp ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Depending on the radiating properties, a body will be opaque when X = 0, a + p = 1 P = 0, x = 0 and a = 1 P = 0, x = 1 and a = 0 P=1, x = 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, x = 0 and a = 0 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat transfer from a hot body to a cold body is directly proportional to the surface area and difference of temperatures between the two bodies. This statement is called First law of thermodynamics Newton's law of heating Newton's law of cooling Stefan's law First law of thermodynamics Newton's law of heating Newton's law of cooling Stefan's law ANSWER DOWNLOAD EXAMIANS APP
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 0.45 0.55 0.75 0.4 0.45 0.55 0.75 0.4 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Unit of thermal conductivity in M.K.S. units is 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 K cal/hr m² °C K cal/kg m² °C ANSWER DOWNLOAD EXAMIANS APP