The process of heat transfer from one particle of the fluid to another by the actual movement of the fluid particles caused by some mechanical means, is known as Forced convection Free convection Conduction Radiation TRUE ANSWER : ? YOUR ANSWER : ?
All radiations in a black body are Absorbed Refracted Transmitted Reflected TRUE ANSWER : ? YOUR ANSWER : ?
When absorptivity (α) = 1, reflectivity (ρ) = 0 and transmissivity (τ) = 0, then the body is said to be a Grey body White body Opaque body Black body TRUE ANSWER : ? YOUR ANSWER : ?
Free convection flow depends on All of these Density Coefficient of viscosity Gravitational force TRUE ANSWER : ? YOUR ANSWER : ?
Kirchhoff's law states that 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 The wave length corresponding to the maximum energy is proportional to the absolute temperature The total radiation from a black body per second per unit area is directly proportional to the fourth power of the absolute temperature None of these TRUE ANSWER : ? YOUR ANSWER : ?
Fouling factor is used In case of Newtonian fluids In heat exchanger design as a safety factor When a liquid exchanges heat with a gas None of these TRUE ANSWER : ? YOUR ANSWER : ?
The rate of energy transferred by convection to that by conduction is called Biot number Stanton number Nusselt number Peclet number TRUE ANSWER : ? YOUR ANSWER : ?
In free convection heat transfer transition from laminar to turbulent flow is governed by the critical value of the Reynold's number, Grashoff's number Reynold's number Grashoff's number Prandtl number, Grashoff's number TRUE ANSWER : ? YOUR ANSWER : ?
In counter flow heat exchangers One fluid is in hottest state and other in coldest state at inlet Both the fluids at exit are in their hottest state Both the fluids at inlet are in their hottest state Both the fluids at inlet (of heat exchanger where hot fluid enters) are in their coldest state TRUE ANSWER : ? YOUR ANSWER : ?
According to Stefan Boltzmann law, the total radiation from a black body per second per unit area is directly proportional to the Cube of the absolute temperature Square of the absolute temperature Fourth power of the absolute temperature Absolute temperature TRUE ANSWER : ? YOUR ANSWER : ?