Q. According to Stefan's law, the total radiation from a black body per second per unit area is directly proportional to the fourth power of the absolute temperature.

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Q. In electrolux refrigerator

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Q. Two long parallel surfaces each of emissivity 0.7 are maintained at different temperatures and accordingly have radiation heat exchange between them. It is desired to reduce 75% of the radiant heat transfer by inserting thin parallel shields of emissivity 1 on both sides. The number of shields should be

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Q. The C.O.P. of a Carnot refrigerator in winter will be __________ as compared to C.O.P. in summer.

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Q. Which of the following statement is correct?

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Q. When the temperature of the surrounding is higher than the temperature of the body, then the heat loss by convection from the body to the surrounding will be

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Q. If a gas is to be liquified, its temperature must be

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Q. The thermostatic expansion valve is used in __________ type of evaporators.

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Q. Thermal conductivity of a material may be defined as the

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Q. During sensible heating of air, specific humidity remains constant.

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Q. Air refrigeration cycle is used in

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Q. Reynolds number is the ratio of

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Q. The wet bulb depression is zero when relative humidity is

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Q. The sensible heat during humidification process decreases.

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Q. According to Newton's law of cooling, the heat transfer from a hot body to a cold body is

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Q. The freezing point of carbon dioxide is equal to boiling point of R-12.

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Q. The condition of refrigerant as it leaves the compressor in a vapour compression system is

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Q. The super-heating in a refrigeration cycle

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Q. A boot-strap air cooling system has

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Q. The boiling point of __________ is -10.5°C.

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