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速度与机械运动

> 如图所示的装置处于静止状态．甲、乙两物体的密度分别为ρ 甲、ρ 乙，其体积之比V 甲：V 乙=3：4，质量之比m 甲：m 乙=4：5．若不计绳重、轮重及摩擦，则下列说法正确的是 A.甲、乙的密度之比ρ甲：ρ乙=3：5 B.甲、乙受到的合力都为零 C.绳子对乙的拉力等于G甲 D.乙对水平地面的压力与乙的重力之比为3：5

问题：

发布时间：2024-09-09

如图所示的装置处于静止状态．甲、乙两物体的密度分别为ρ _甲、ρ _乙，其体积之比V _甲：V _乙=3：4，质量之比m _甲：m _乙=4：5．若不计绳重、轮重及摩擦，则下列说法正确的是

A.甲、乙的密度之比ρ甲：ρ乙=3：5
B.甲、乙受到的合力都为零
C.绳子对乙的拉力等于G甲
D.乙对水平地面的压力与乙的重力之比为3：5

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