A 、 B 两船的质量均为 m ，静止在平静的湖面上。现 A 船中质量为 m3 的人从 A 船跳到 B 船，再从 B 船跳回 A 船，经 n 次跳跃后，人停在 B 船上。不计空气和水的阻力，下列说法正_刷题宝

题干

A 、 B 两船的质量均为 m ，静止在平静的湖面上。现 A 船中质量为

m

3

的人从 A 船跳到 B 船，再从 B 船跳回 A 船，经 n 次跳跃后，人停在 B 船上。不计空气和水的阻力，下列说法正确的是（）

A： $A$ ， $B$ 两船组成的系统动量守恒

B：A， $B$ 两船和人组成的系统水平方向动量守恒

C：人停在 $B$ 船上后 $A$ ， $B$ 两船的速度大小之比为 $1 : 1$

D：人停在 $B$ 船上后 $A$ ， $B$ 两船的速度大小之比为 $4 : 3$

上一题下一题 0.0难度选择题更新时间:2019-08-21 10:10:07

答案(点此获取答案解析）

B,D

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