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 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 First law of thermodynamics Newton's law of heating ANSWER DOWNLOAD EXAMIANS APP
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 Square of the absolute temperature Absolute temperature Cube of the absolute temperature Fourth power of the absolute temperature Square of the absolute temperature Absolute temperature Cube of the absolute temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Depending on the radiating properties, body will be transparent when(Where a = absorptivity, p = reflectivity, x = transmissivity) X = 0, a + p = 1 P = 0, x= 1, and a = 0 P = 0, x = 0 and a = 1 P=1, x = 0, and a = 0 X = 0, a + p = 1 P = 0, x= 1, and a = 0 P = 0, x = 0 and a = 1 P=1, x = 0, and a = 0 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer 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. This statement is known as Planck's law Kirchhoff's law Wien's law Stefan's law Planck's law Kirchhoff's law Wien's law Stefan's law ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A cube at high temperature is immersed in a constant temperature bath. It loses heat from its top, bottom and side surfaces with heat transfer coefficients of h₁, h₂ and h₃ respectively. The average heat transfer coefficient for the cube is 1/h₁ + 1/h₂ + 1/h₃ None of these (h₁.h₂.h₃)1/3 h₁ + h₂ + h₃ 1/h₁ + 1/h₂ + 1/h₃ None of these (h₁.h₂.h₃)1/3 h₁ + h₂ + h₃ ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer When α is absorptivity, ρ is reflectivity and τ is transmissivity, then for a diathermanous body, α = 0, ρ = 0 and τ = 1 α = 1, ρ = 0 and τ = 0 α + ρ = 1 and τ = 0 α = 0, ρ = 1 and τ = 0 α = 0, ρ = 0 and τ = 1 α = 1, ρ = 0 and τ = 0 α + ρ = 1 and τ = 0 α = 0, ρ = 1 and τ = 0 ANSWER DOWNLOAD EXAMIANS APP