科学 (21 22:57:24)
问题描述:
科学 (21 22:57:24)
凸透镜的焦距怎么找
具体点
答
记住:一倍焦区分虚实,两倍焦区分大小
即u>2f 成倒立缩小实像
u=2f 成倒立等大实像
f
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