Question: A perfect black body is a perfect __________ of radiation.
[A].absorber
emitter
both (a) & (b)
neither (a) nor (b)
[A].
[B].
[C].
[D].
Answer: Option C
Explanation:
No answer description available for this question.
Heat Transfer
Nusselt number is a function of Prandtl number and __________ number of fluid in natural convection heat transfer.
Question: Nusselt number is a function of Prandtl number and __________ number of fluid in natural convection heat transfer.
[A].Grashoff
Biot
Stantan
Reynolds
[A].
[B].
[C].
[D].
Answer: Option A
Explanation:
No answer description available for this question.
__________ chart is known as transient heat conduction chart.
Question: __________ chart is known as transient heat conduction chart.
[A].Dirhing’s
Heisler’s
Mollier’s
Cox
[A].
[B].
[C].
[D].
Answer: Option A
Explanation:
No answer description available for this question.
With increase in temperature, the thermal conductivity of non-metallic amorphous solids
Question: With increase in temperature, the thermal conductivity of non-metallic amorphous solids
[A].decreases
increases
remains constant
first decreases upto certain temperature and then increases
[A].
[B].
[C].
[D].
Answer: Option B
Explanation:
No answer description available for this question.
With increase in temperature, the thermal conductivity of most liquids
Question: With increase in temperature, the thermal conductivity of most liquids
[A].increases
decreases
remains same
first increases upto a certain temperature and then becomes constant
[A].
[B].
[C].
[D].
Answer: Option B
Explanation:
No answer description available for this question.
For flow over a flat plate, the ratio of thermal boundary layer thickness, ‘xt’ and hydrodynamic boundary layer thickness ‘x’ is equal to (where, NPr = Prandtl number)
Question: For flow over a flat plate, the ratio of thermal boundary layer thickness, ‘xt’ and hydrodynamic boundary layer thickness ‘x’ is equal to (where, NPr = Prandtl number)
[A].NPr
NPr1/3
NPr-1
NPr-1/3
[A].
[B].
[C].
[D].
Answer: Option B
Explanation:
No answer description available for this question.
Fluid motion in the natural convection heat transfer between a solid surface and a fluid in contact with it, results from the
Question: Fluid motion in the natural convection heat transfer between a solid surface and a fluid in contact with it, results from the
[A].existence of thermal boundary layer.
temperature gradient produced due to density difference
buoyancy of the bubbles produced at active nucleation site.
none of these.
[A].
[B].
[C].
[D].
Answer: Option D
Explanation:
No answer description available for this question.
Extended heat transfer surface like fins are used to increase the heat transfer rate. Fin efficiency is defined as the ratio of heat transferred across the fin surface to the theoretical heat transfer across an equal area held at the
Question: Extended heat transfer surface like fins are used to increase the heat transfer rate. Fin efficiency is defined as the ratio of heat transferred across the fin surface to the theoretical heat transfer across an equal area held at the
[A].surrounding temperature.
average temperature of the fin.
temperature of the fin end.
constant temperature equal to that of the base
[A].
[B].
[C].
[D].
Answer: Option D
Explanation:
No answer description available for this question.
In Biot number, the characteristic length used is the ratio of the __________ of the solid.
Question: In Biot number, the characteristic length used is the ratio of the __________ of the solid.
[A].volume to surface area
perimeter to surface area
surface area to volume
surface area to perimeter
[A].
[B].
[C].
[D].
Answer: Option A
Explanation:
No answer description available for this question.
A backward feed multiple effect evaporator is better than forward feed for concentrating cold feed, because it provides
Question: A backward feed multiple effect evaporator is better than forward feed for concentrating cold feed, because it provides
[A].higher economy
lower capacity
both (a) & (b)
lower economy
[A].
[B].
[C].
[D].
Answer: Option A
Explanation:
No answer description available for this question.