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प्रश्न
Explain the following
In winter, water tanks (or ocean) start freezing from the surface and not from the bottom.
उत्तर
In winters, when temperature falls, the surface of water in the tank contracts, becomes denser and sinks to the bottom. A circulation is thus set up until the entire water in the tank reaches its maximum density at 4°C. If the temperature falls further, then the top layer expands and remains on the top till it freezes. Thus, water in a tank starts freezing from the top and not from the bottom.
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संबंधित प्रश्न
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