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प्रश्न
Explain, why are big tubs of water kept in underground cellars for storing fresh fruit and vegetables in cold countries.
उत्तर
During sub zero temperatures, the water within the cells of fruits and vegetables freezes and hence damages them. To avoid such a damage the huge water tubs are kept. The water gives off 4200 J of heat energy for every one kg for 1°C fall is temperature. Thus, it does not allow the temperature of cell to fall below 0°C and hence there is no damage to fresh fruits or vegetables.
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संबंधित प्रश्न
Explain the melting point ?
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