题干

小明和小忠想把一条弹性绳拉开,使弹性绳两端的拉环能分别套在相隔一段距离的两根柱子上,用来晒衣服。现有两种办法:一种是按图甲的方法做;另一种是按图乙的方法做。关于这两种做法下列说法正确的是(        )

  

A:图甲中每个人所用的力比图乙中每个人所用力要小

B:图乙中每个人所用的力比图甲中每个人所用力要小

C:图甲中每个人所用的力与图乙中每个人所用力相同

D:条件不足,无法比较图甲中每个人所用的力与图乙中每个人所用力的大小

上一题 下一题 0.0难度 选择题 更新时间:2018-02-07 09:44:46

答案(点此获取答案解析)

B

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