29. Moisture would find its way into insulation by vapor pressure unless it is prevented by
A.High thickness of insulation
B.High vapour pressure
C.Less thermal conductivity insulator
D.A vapor seal

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30. LMTD in case of counter flow heat exchanger as compared to parallel flow heat exchanger is
A.Higher
B.Lower
C.Same
D.Depends on the area of heat exchanger

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31. The amount of radiation mainly depends on
A.Nature of body
B.Temperature of body
C.Type of surface of body
D.All of the above

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32. Absorptivity of a body will be equal to its emissivity
A.At all temperatures
B.At one particular temperature
C.When system is under thermal equilibrium
D.At critical temperature

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33. Cork is a good insulator because it has
A.Free electrons
B.Atoms colliding frequency
C.Low density
D.All of the above

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34. The rate of energy emission from unit surface. area through unit solid angle, along a normal to the surface, is known as
A.Emissivity
B.Transmissivity
C.Reflectivity
D.Intensity of radiation

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35. 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. This statement is known as
A.Krichoff's law
B.Stefan's law
C.Wien' law
D.Planck's law

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