Q. The subcooling in a refrigeration cycle

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Q. Nusselt number (NN) is given by

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Q. During sensible cooling of air __________ decreases.

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Q. According to Dalton's law of partial pressures, (where pb = Barometric pressure, pa = Partial pressure of dry air, and pv = Partial pressure of water vapour)

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Q. The heat transfer by conduction through a thick sphere is given by

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Q. The relative humidity is defined as

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Q. Fourier's law of heat conduction is (where Q = Amount of heat flow through the body in unit time, A = Surface area of heat flow, taken at right angles to the direction of heat flow, dT = Temperature difference on the two faces of the body, dx = Thickness of the body, through which the heat flows, taken along the direction of heat flow, and k = Thermal conductivity of the body)

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Q. The heat transfer by conduction through a thick sphere is same as through a thick cylinder.

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Q. The humidity ratio or specific humidity is the mass of water vapour present in

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Q. The formation of frost on cooling coils in a refrigerator

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Q. The by-pass factor for a cooling coil

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Q. The difference between dry bulb temperature and wet bulb temperature, is called

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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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