Heat and Mass Transfer Unit of thermal conductivity in M.K.S. units is K calm/hr °C K cal m/hr m² °C K cal/kg m² °C K cal/hr m² °C K calm/hr °C K cal m/hr m² °C K cal/kg m² °C K cal/hr m² °C ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Two long parallel surfaces each of emissivity 0.7 are maintained at different temperatures and accordingly have radiation heat exchange between them. It is desired to reduce 75% of the radiant heat transfer by inserting thin parallel shields of emissivity 1 on both sides. The number of shields should be Three Four One Two Three Four One Two 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= 1, T = 0 and a = 0 P = 0, x = 1 and a = 0 P = 0, x = 0 and a = 1 X = 0, a + p = 0 P= 1, T = 0 and a = 0 P = 0, x = 1 and a = 0 P = 0, x = 0 and a = 1 X = 0, a + p = 0 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. (dx/dT) k. (dx/dT) k. (dT/dx) (dT/dx) k. k. (dx/dT) k. (dx/dT) k. (dT/dx) (dT/dx) k. ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The ratio of the energy absorbed by the body to total energy falling on it is called Absorptivity Emissivity Emissive power Absorptive power Absorptivity Emissivity Emissive power Absorptive power ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Cork is a good insulator because it has Porous body Atoms colliding frequency Free electrons Low density Porous body Atoms colliding frequency Free electrons Low density ANSWER DOWNLOAD EXAMIANS APP
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