高中物理课本“弹性碰撞”一节中,所提的演示实验是质量相等的小球(钢球或瓷球)能量互相传递:A球碰撞B球后,A球即静止,能量传给了B球,使B球等速率开始运动(指初速。)B球再返回时,碰撞A球,则B球静止A球运动,如此反复。这要求做到对心碰撞(正碰)。我们在做演示实验中,往往不能一次成功,且反复碰撞的次数总不多——很快就斜碰了,故而要求一球的能量全部传递给另一球——一动一静,就做不到了,这不能不说是一个很大的缺陷。如果采用下法(用正碰器演示)就能保证每次做到正碰。就是用一木棒(或金属棒)作轴,在小球二边各加一支架(用硬塑或金属均可,最好牢固而密度小),两球与轴的距离相等,这样就不会斜碰了,且一动一静能 In the high school physics textbook “Elastic Collisions” section, the demonstration experiment is that the balls of the same quality (balls or porcelain balls) transfer energy to each other: After the ball hits ball B, the ball A is stationary and energy is transmitted to B ball, so that the rate of B ball began to move (refer to the muzzle velocity.) B ball back again, hit the A ball, B ball still A ball movement, so repeated. This requires a collision of hearts (positive collision). In our demonstration experiment, we often cannot succeed at one time, and the number of repeated collisions is always small—it quickly slants, and therefore requires all the energy of one ball to be passed on to the other ball. This can’t be said to be a big flaw. If you use the following method (showing with a positive touch), you can ensure that you touch each time. It is to use a wooden rod (or metal rod) as the axis, on each side of the small ball plus a bracket (hard plastic or metal can be, the best solid and small density), the distance between the two balls and the shaft is equal, so it is not Will be slanted, and a static and a static