Q. For evaporators and condensers, for the given conditions, the logarithmic mean temperature difference (tm) for parallel flow is __________ that for counter flow.

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Q. A vapour absorption refrigerator uses __________ as a refrigerant.

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Q. Thermal conductivity of air increases with rise in temperature.

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Q. The material of pipe lines for a system using ammonia as a refrigerant should be copper.

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Q. The wave length corresponding to the maximum energy is inversely proportional to the absolute temperature. This statement is called Planck's law.

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Q. The sensible heat gain is due to the __________ difference between the fresh air and the air in space.

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Q. During cooling and dehumidification, dry bulb temperature

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Q. The coefficient of performance of electrolux refrigerator is the ratio of

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Q. The sulphur sticks, in case of leakage of ammonia refrigerant, gives white smoke.

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Q. During gas charging in an ammonia vapour compression system, the connection is made at the compressor outlet.

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Q. The wet bulb temperature at 100% relative humidity is __________ dew point temperature.

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Q. The use of heat exchangers is made in

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Q. In a heat exchanger with one fluid evaporating or condensing, the surface area required is least in

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Q. Which of the following statement is correct?

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Q. The horizontal and uniformly spaced lines on a psychrometric chart indicates relative humidity.

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Q. The condition of refrigerant after passing through the expansion or throttle valve, in a vapour compression system is

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Q. The process of adding moisture to the air, without change in its dry bulb temperature, is known as humidification.

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Q. In case of liquids and gases, the heat transfer takes place according to

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Q. The logarithmic mean temperature difference (tm) is given by (where Δt1 and Δt2 are temperature differences between the hot and cold fluids at entrance and exit)

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Q. The radiation emitted by a black body is known as

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