Heat and Mass Transfer According to Newton's law of cooling, the heat transfer from a hot body to a cold body is Either (A) or (B) Directly proportional to the difference of temperatures between the two bodies Directly proportional to the surface area Both (A) and (B) Either (A) or (B) Directly proportional to the difference of temperatures between the two bodies Directly proportional to the surface area Both (A) and (B) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer If the energy radiated per second per sq. cm. of the surface for wave lengths lying between λ, and λ + dλ is represented by (eλ.dλ), then eλ is called Emissivity Emissive power Absorptive power None of these Emissivity Emissive power Absorptive power None of these 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. k. (dT/dx) k. (dT/dx) (dx/dT) k. (dx/dT) k. k. (dT/dx) k. (dT/dx) (dx/dT) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A perfect black body is one which Is black in colour Transmits all heat radiations Absorbs heat radiations of all wave lengths falling on it Reflects all heat Is black in colour Transmits all heat radiations Absorbs heat radiations of all wave lengths falling on it Reflects all heat ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Which of the following is a case of steady state heat transfer? Air preheaters Heating of building in winter None of these I.C. engine Air preheaters Heating of building in winter None of these I.C. engine ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer When heat is transferred by molecular collision, it is referred to as heat transfer by Convection Radiation Conduction Scattering Convection Radiation Conduction Scattering ANSWER DOWNLOAD EXAMIANS APP