Q. A reversible engine has ideal thermal efficiency of 30%. When it is used as a refrigerating machine with all other conditions unchanged, the coefficient of performance will be

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Q. Which of the following refrigerant is highly toxic and flammable?

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Q. The unit of Stefan-Boltzmann constant is

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Q. In a vapour compression system, the condition of refrigerant is dry saturated vapour

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Q. An evaporator is also known as

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Q. The rate of heat flow through a body is . The term is known as temperature gradient.

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Q. Oil separator in a refrigeration cycle is installed

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Q. In larger industrial and commercial reciprocating compression systems, refrigerent widely used is

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Q. The coefficient of performance of a domestic refrigerator is __________ as compared to a domestic air-conditioner.

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Q. The process of heat transfer from one particle of the body to another is called conduction, when the particles of the body

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Q. The human body feels comfortable when the heat stored in the body is

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Q. A Bell Coleman refrigerator working on dense air system as compared to open air system, for the same range of temperature, results in __________ power per tonne of refrigeration.

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Q. The amount of heat flow through a body by conduction is

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Q. The emissive power of a body depends upon its

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Q. An electric cable of aluminium conductor (k = 240 W/mK) is to be insulated with rubber (k = 0.15 W/mK). The cable is to be located in air (h = 6 W/m²). The critical thickness of insulation will be

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Q. A cube at high temperature is immersed in a constant temperature bath. It loses heat from its top, bottom and side surfaces with heat transfer coefficients of h1, h2 and h3 respectively. The average heat transfer coefficient for the cube is

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Q. The dehumidification process, on the psychrometric chart, is shown by

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Q. The vertical and uniformly spaced lines on a psychrometric chart indicates

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Q. A furnace is made of a red brick wall of thickness 0.5 m and conductivity 0.7 W/mK. For the same heat loss and temperature drop, this can be replaced by a layer of diatomite earth of conductivity 0.14 W/mK and thickness

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Q. In a refrigeration system, the expansion device is connected between the

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