A frozen-food company freezes its spinach by first compressing it into large slabs and then exposing the slab of spinach to a low-temperature cooling medium. The large slab of compressed spinach is initially at a uniform temperature of 21?C; it must be reduced to an average temperature over the entire slab of ??34?C. The temperature at any part of the slab, however, must never drop below ??51?C. The cooling medium which passes across both sides of the slab is at a constant temperature of ??90?C. The following data may be used for the spinach: density = 80 kg/m3; thermal conductivity = 0.87 W/(m K); specific heat = 2100 J/(kg K). Present a detailed analysis outlining a method estimate the maximum thickness of the slab of spinach that can be safely cooled in 60 min.GIVENLarge slabs of spinach are exposed to a low-temperature cooling mediumInitial uniform temperature (To) = 21?CAverage temperature must be reduced to ??34?CThe temperature at any part must never drop below ??51?CCooling medium temperature (T??) = ??90?CDensity of spinach (ρ) = 80 kg/m3Thermal conductivity (k) = 0.87 W/(m K)Specific heat (c) = 2100 J/(kg K)ASSUMPTIONSOne dimensional conduction through the slabConstant and uniform thermal propertiesThe average temperature within the slab is equal to the average of the center and surfaceTemperatures

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Coolng Medlum T.-- 90°C /1/1 Spinach 2L