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प्रश्न
Why do the farmers fill their fields with water on a cold winter night?
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उत्तर
In the absence of water, if on a cold winter night the atmospheric temperature falls below 0oC,
the water in the fine capillaries of plant will freeze, so the veins will burst due to the increase in
the volume of water on freezing. As a result, plants will die and the crop will be destroyed. In
order to save the crop on such cold nights, farmers fill their fields with water because water has
high specific heat capacity, so it does not allow the temperature in the surrounding area of plants
to fall up to 0oC.
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