Heat & Mass Transfer MCQ Question with Answer

Question No : 15
Heat flows from one body to other when they have

Question No : 16
The rate of heat flow through a body is Q = [kA (T₁ - T₂)]/x. The term x/kA is known as

Question No : 17
A perfect black body is one which

Question No : 18
Planck's law holds good for

Question No : 19
In counter flow heat exchangers

Question No : 20
The ratio of the thickness of thermal boundary layer to the thickness of hydrodynamic boundary layer is equal to (Prandtl number) n, where n is equal to

Question No : 21
The thermal diffusivities for solids are generally