“小船过河”问题是运动的合成与分解中最常见的典型题.通常已知流水速度u和船在静水中的速度v(>u),讨论①船过河的最短时间;②船过河的最小位移;③船到达对岸上游或下游指定地点,船的航向——速度v_合的方向与河岸之间的夹角及船的过河时间.如 The problem of “boat crossing the river” is the most common typical problem in the synthesis and decomposition of the movement. It is usually known that the velocity of the water u and the velocity v (> u) of the ship in the still water discuss the shortest time when the river crosses the river; The minimum displacement of the ship across the river; ③ the ship reaches the designated location upstream or downstream of the other side, the course of the ship - the direction of the speed v_ and the angle between the river bank and the river crossing time.