Heat and Mass Transfer In case of liquids and gases, the heat transfer takes place according to Convection Conduction None of these Radiation Convection Conduction None of these Radiation ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A composite slab has two layers of different materials with thermal conductivities k₁ and k₂. If each layer has the same thickness, then the equivalent thermal conductivity of the slab will be (k₁ + k₂) 2 k₁ k₂/ (k₁ + k₂) (k₁ + k₂)/ k₁ k₂ k₁ k₂ (k₁ + k₂) 2 k₁ k₂/ (k₁ + k₂) (k₁ + k₂)/ k₁ k₂ k₁ k₂ ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The value of the wave length for maximum emissive power is given by Planck’s law Kirchhoff’s law Stefan’s law Wine’s law Planck’s law Kirchhoff’s law Stefan’s law Wine’s law ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A perfect black body is one which Absorbs heat radiations of all wave lengths falling on it Is black in colour Reflects all heat Transmits all heat radiations Absorbs heat radiations of all wave lengths falling on it Is black in colour Reflects all heat Transmits all heat radiations ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Two balls of same material and finish have their diameters in the ratio of 2: 1 and both are heated to same temperature and allowed to cool by radiation. Rate of cooling by big ball as compared to smaller one will be in the ratio of 0.042361111111111 0.16736111111111 0.043055555555556 0.084027777777778 0.042361111111111 0.16736111111111 0.043055555555556 0.084027777777778 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. A. (dx/dT) k. (dT/dx) k. A. (dT/dx) k. (dx/dT) k. A. (dx/dT) k. (dT/dx) k. A. (dT/dx) ANSWER DOWNLOAD EXAMIANS APP