Heat transfer coefficient between water and surroundings

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Reference no: EM13718445

A hot-water cylinder contains 150 liters of water. It is insulated, and its outer surface has an area of 3.5 m^2. It is located in an area where the ambient air is 25⁰C, and the overall heat transfer coefficient between the water and the surroundings is 1.0 W/m2 K, based on outer surface area. If there is a power failure, how long will it take the water to cool from 65⁰C to 40⁰C? Take the density of water as 980 kg/m3 and its specific heat as 4180 J/kg K.

Reference no: EM13718445

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