毛钱管(牛顿管)是演示轻重不同的物体在真空中自由下落速度相同的仪器。目前,配发的毛钱管,在实验中存在如下问题:一是毛钱管在转为竖直方向的过程中,转速较大,学生很难清楚地观察到羽毛和钱同时下落的现象;二是快速转动毛钱管,由于惯性,毛、钱在下落时与管壁碰撞,且有摩擦,从而二者不是沿竖 A cashier tube (Newtonian tube) is an instrument that demonstrates the same free-falling speed of different objects in a vacuum. At present, dispensing cashmere tubes have the following problems in the experiment: First, in the process of converting the cash tube to the vertical direction, the rotation speed is relatively large, and it is difficult for the students to clearly observe the simultaneous falling of feathers and money; The second is the rapid rotation of the money tube. Because of inertia, hair and money collide with the tube wall when they fall, and there is friction, so the two are not along the vertical