Q. Defrosting of a refrigerator may be done by stopping the compressor for a short period.

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Q. In aqua-ammonia and Lithium-bromide water absorption refrigeration systems, the refrigerants are respectively

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Q. As relative humidity decreases, the dew point temperature will be __________ wet bulb temperature.

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Q. The process of heat transfer from a hot body to a cold body, in a straight line, without affecting the intervening medium, is called radiation.

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Q. Reynolds number (RN) is given by (where h = Film coefficient, l = Linear dimension, V = Velocity of fluid, k = Thermal conductivity, t = Temperature, ρ = Density of fluid, cp = Specific heat at constant pressure, and μ = Coefficient of absolute viscosity)

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Q. The optimum effective temperature for human comfort is

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Q. The wet bulb temperature lines, on the psychrometric chart, are curved lines.

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Q. The sensible heat factor during cooling and dehumidification process is given by (where h1 = Enthalpy of air entering the cooling coil, h2 = Enthalpy of air leaving the cooling coil, and hA = Enthalpy of air at the end of dehumidification process)

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Q. Thermal diffusivity is a

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Q. The condition of refrigerant after leaving the compressor and before entering the condenser is superheated vapour.

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Q. The total radiation from a black body per second per unit area is __________ fourth power of the absolute temperature. This statement is known as Stefan-Boltzmann law.

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Q. In a psychrometric process, the sensible heat added is 30 kJ/s and the latent heat added is 20 kJ/s. The sensible heat factor for the process will be

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Q. The amount of radiation mainly depends upon the

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Q. For ammonia refrigerating systems, the tubes of a shell and tube condenser are made of

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Q. The highest thermal diffusivity is of

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Q. While designing the refrigeration system of an aircraft, the prime consideration is that the

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Q. The heat transfer takes place according to

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Q. An electrolux refrigerator is called a __________ absorption system.

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Q. The heat transfer by radiation __________ a medium.

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Q. Thermal conductivity of water __________ with rise in temperature.

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