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速度与机械运动

> 有关下面各图的说法中正确的是 A.甲图：空气疏密相间的波动向远处传播，就形成了声波 B.乙图：变速自行车上坡时想省力，后轴的齿轮应该换用较大的 C.丙图：钢笔错位是因为光的直线传播 D.丁图：凸透镜成虚像时，物和虚像在凸透镜同一侧

问题：

发布时间：2024-09-10

有关下面各图的说法中正确的是

A.甲图：空气疏密相间的波动向远处传播，就形成了声波
B.乙图：变速自行车上坡时想省力，后轴的齿轮应该换用较大的
C.丙图：钢笔错位是因为光的直线传播
D.丁图：凸透镜成虚像时，物和虚像在凸透镜同一侧

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