Estimate the time required to freeze a 3 cm thickness of water due to nocturnal radiation with ambient air and initial water temperature at 4?C. Neglect evaporation effects.GIVENWater exposed to nocturnal radiation and airInitial water temperature (Twi) and ambient air temperature (T??) = 4?CASSUMPTIONSThe thermal capacitance of the ice is negligibleThe energy required to lower the temperature of the water to the freezing point is negligible compared to the latent heat of fusionNatural convection from the upper and lower surfaces of the ice layer is negligibleEffective sky temperature (Ts) = 0 KIce surface behaves as a blackbody (εr =1.0)

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T= 4° C Alr To TCE Tw = 4° C Water