Unsteady state of heat flow occurs in
A.Flow of heat through furnace walls
B.Flow of heat through insulated pipe with constant surface temperature
C.Annealing of castings
D.Flow of heat through refrigerator walls
E.None of the above
A.Flow of heat through furnace walls
B.Flow of heat through insulated pipe with constant surface temperature
C.Annealing of castings
D.Flow of heat through refrigerator walls
E.None of the above
A.submarines
B.rockets
C.satellites
D.nuclear war heads
A.0?K
B.0?F
C.0?C
D.the same as that of the human body
A.Prandtl number
B.Reynolds number
C.Nusselt number
D.Pacelet number
E.Grashoff number
A.Planck’s law
B.D’Alembert’s rule
C.Kirchhoff’s law
D.Stefan law
E.Wein’s law
A.By using insulated vessels
B.By using small quantities
C.By using deoxidisers
D.By using vacuum
E.By using low intensity heating
A.One fluid exchanging with another fluid of the same chemical composition
B.The section of heat exchanger which will cause temperature drop of one degree centigrade
C.The section of heat exchanger where heat transfer surface area is one square metre
D.The equivalent length of tubes in case the heat exchange was for a temperature difference of 1?C
E.Condition when the change in temperature of 1?C numerically equals the average driving force.
A.more than 1
B.1
C.less than 1
D.0.5
A.Air to heavy tars
B.Air to carbondioxide
C.Steam to oil
D.Steam condensers
A.increase
B.decrease
C.remain constant