160 Important Heat And Mass Transfer MCQ Question and Answer | PDF Free Download
1.The ratio of Nusselt number and the product of Reynold's number and Prandtl number is equal to
- AStanton number
- BBiot number
- CPeclet number
- DGrashoff number
2.A steam pipe is to be lined with two layers of insulating materials of different thermal conductivities. For the minimum heat transfer,
- AThe better insulation must be put inside
- BThe better insulation must be put outside
- COne could place either insulation on either side
- DOne should take into account the steam temperature before deciding as to which insulation is put where
3.In a heat exchanger with one fluid evaporating or condensing, the surface area required is least in
- AParallel flow
- BCounter flow
- CCross flow
- DAll of these
4.Absorptivity of a body will be equal to its emissivity
- AAt all temperatures
- BAt one particular temperature
- CWhen system is under thermal equilibrium
- DAt critical temperature