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> 农谚说“霜前冷,雪后寒”.你能运用所学的物态变化知识,解释这一现象吗?-八年级物理
农谚说“霜前冷,雪后寒”.你能运用所学的物态变化知识,解释这一现象吗?-八年级物理
题目简介
农谚说“霜前冷,雪后寒”.你能运用所学的物态变化知识,解释这一现象吗?-八年级物理
题目详情
农谚说“霜前冷,雪后寒”.你能运用所学的物态变化知识,解释这一现象吗?
题型:问答题
难度:中档
来源:不详
答案
答:①霜是初冬季节空气中的水蒸气到了夜晚遇强冷空气凝华成小冰晶,附着在地面上形成的,霜前的温度必须足够低(0℃以下),故感到冷.
②雪是高空中的水蒸气遇强冷凝华成小冰晶后下降到地面,下雪时气温本来就很低,而下雪后的熔化过程要吸收热量,使地面上方空气的温度降低,所以有雪后寒的感觉.
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题目简介
农谚说“霜前冷,雪后寒”.你能运用所学的物态变化知识,解释这一现象吗?-八年级物理
题目详情
答案
②雪是高空中的水蒸气遇强冷凝华成小冰晶后下降到地面,下雪时气温本来就很低,而下雪后的熔化过程要吸收热量,使地面上方空气的温度降低,所以有雪后寒的感觉.