Heat and Mass Transfer Thermal diffusivity of a substance is Inversely proportional to density of substance Directly proportional to the thermal conductivity All of these Inversely proportional to specific heat Inversely proportional to density of substance Directly proportional to the thermal conductivity All of these Inversely proportional to specific heat 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. (dT/dx) k. k. (dT/dx) (dx/dT) k. (dx/dT) k. (dT/dx) k. k. (dT/dx) (dx/dT) k. (dx/dT) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The transfer of heat by molecular collision is known as None of these Conduction Radiation Convection None of these Conduction Radiation Convection ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of water _________ with rise in temperature. Remain same Decreases May increase or decrease depending upon temperature Increases Remain same Decreases May increase or decrease depending upon temperature Increases ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Planck’s law holds good for all coloured bodies black bodies All of these polished bodies all coloured bodies black bodies All of these polished bodies 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) P=1, x = 0, and a = 0 P = 0, x = 0 and a = 1 X = 0, a + p = 1 P = 0, x= 1, and a = 0 P=1, x = 0, and a = 0 P = 0, x = 0 and a = 1 X = 0, a + p = 1 P = 0, x= 1, and a = 0 ANSWER DOWNLOAD EXAMIANS APP