题一个质量为M的人手里拿着一根长为L的轻绳,绳子的另一端连接一个质量为m的小球.现人使球在竖直平面内做圆周运动,已知小球恰好可以通过最高点,试求人对地面的压力大小的范围. A person of mass M holds a light rope of length L in his hand, and the other end of the rope is connected to a ball of mass m. Now the person makes the ball move in a circular plane in a vertical plane. It is known that the ball just happens to be You can try to ask people for the range of pressure on the ground through the highest point.