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速度与机械运动

> 如图所示甲、乙两个装置，已知A在地面上滑动时所受的摩擦力为40牛（不考虑绳与滑轮的摩擦）．要使A向右匀速滑动，拉力F 甲与F 乙的大小分别为 A.40牛，20牛 B.20牛，40牛 C.40牛，40牛 D.20牛，20牛

问题：

发布时间：2024-09-07

如图所示甲、乙两个装置，已知A在地面上滑动时所受的摩擦力为40牛（不考虑绳与滑轮的摩擦）．要使A向右匀速滑动，拉力F _甲与F _乙的大小分别为

A.40牛，20牛
B.20牛，40牛
C.40牛，40牛
D.20牛，20牛

参考答案：

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