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Matter in Our Surroundings — Science STD 9 — Question

CBSE BoardEnglish MediumSTD 9ScienceMatter in Our Surroundings3 Marks
Question
On a hot sunny day, why do we feel pleasant sitting under a tree?
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Answer

Tree has lot of leaves which constantly show transpiration. Transpiration is loss of water through small tiny pores of leaves called stomata. When this water comes on the surface of leaf the water evaporates thereby causing cooling effect. Therefore we feel pleasant sitting under the tree on a hot sunny day.

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