Heat and Mass Transfer A grey body is one whose absorptivity Varies with wavelength of the incident ray Varies with temperature Does not vary with temperature and. wavelength of the incident ray Is equal to its emissivity Varies with wavelength of the incident ray Varies with temperature Does not vary with temperature and. wavelength of the incident ray Is equal to its emissivity 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. (dT/dx) k. (dT/dx) k. A. (dx/dT) k. (dx/dT) k. A. (dT/dx) k. (dT/dx) k. A. (dx/dT) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Radiation is the process of heat transfer in which heat flows from a ________, in a straight line, without affecting the intervening medium. Cold body to hot body Larger body to smaller body Hot body to cold body Smaller body to larger body Cold body to hot body Larger body to smaller body Hot body to cold body Smaller body to larger body ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According of Kirchhoff's law Radiant heat is proportional to fourth power of absolute temperature Emissive power depends on 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 Radiant heat is proportional to fourth power of absolute temperature Emissive power depends on 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 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of water _________ with rise in temperature. Increases Remain same May increase or decrease depending upon temperature Decreases Increases Remain same May increase or decrease depending upon temperature Decreases ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Depending on the radiating properties, a body will be white when(Where a = absorptivity, p = reflectivity, x = transmissivity) P = 0, x = 0 and a = 1 X = 0, a + p = 1 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 = 1 P=1, T = 0 and a = 0 P = 0, x = 1 and a = 0 ANSWER DOWNLOAD EXAMIANS APP