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प्रश्न
How does the water kept in an earthen pot (matka) become cold during summer ?
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उत्तर
An earthen pot has a large number of extremely small pores on its wall. Some of the water, continuously keeps seeping through these pores. This water evaporates continuously and absorbs its latent heat, required for vaporization from the earthen pot and the remaining water in the pot. In this way, the remaining water loses heat and gets cooled.
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During summer days, water kept in an earthen pot (pitcher) becomes cool because of the phenomenon of :
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Comment on the following statements:
Evaporation produces cooling.
Evaporation is a fast process and occurs only at the surface of the liquid.
When lemon juice is mixed with soda water, they produce brisk effervescence.
