如图，光滑的平台上有一质量为20kg长为10.0m质量分布均匀的木板AB，其中7.0m伸出平台，O点是其重心．为了不使木板翻倒，起初让一个质量为30kg的小孩站在长木板的右端．关于木板的平衡问题，下列_刷题宝

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如图，光滑的平台上有一质量为20kg长为10.0m质量分布均匀的木板AB，其中7.0m伸出平台，O点是其重心．为了不使木板翻倒，起初让一个质量为30kg的小孩站在长木板的右端．关于木板的平衡问题，下列说法正确的是（　　）

A：若小孩从木板右端向左端走动，小孩在木板上走动的距离不能超过3.0m

B：若小孩从木板右端向左端走动，小孩在木板上走动的距离不能超过5.0m

C：小孩可以在木板上向左随意走动，但决不能从左端离开长木板，否则木板就会翻倒

D：小孩不但可以在木板上向左端随意走动，而且还可以从左端离开木板，木板也不会翻倒

上一题下一题 0.0难度选择题更新时间:2019-11-19 01:36:12

答案(点此获取答案解析）

D

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