Acoustic measurements of bouncing balls and the determination of gravitational acceleration
Acoustic measurements of bouncing balls and the determination of gravitational acceleration
复制标题
弹跳球的声学测量和重力加速度的测定
DOI：
10.1119/1.4801369
复制
发表时间：
2013
期刊：
影响因子：
--
通讯作者：
J. Kuhn
中科院分区：
文献类型：
--
作者：
O. Schwarz;Patrik Vogt;J. Kuhn
可以进行有趣的实验，可以用所谓的超级球或弹力球来探索基本的物理关系。一个例子是在实验中测定重力g。这背后的基本思想由Pape1和Sprokhoff2描述：所有反弹的初始高度和最终高度以及完整的持续时间都是通过球测量一定数量的反弹的。在此基础上，如果忽略球上的空气阻力，则可以近似计算出重力的加速度。然而，在实践中，很明显，测量过程中最后一次反弹的高度是有问题的。进行实验的人要么必须对其高度做出很好的估计，要么必须在测量杆前拍摄弹跳。该方法基于一个重要的假设，即球的每一次反弹都损失了相同百分比的机械能；因此恢复系数k保持不变。
Interesting experiments can be performed and fundamental physical relationships can be explored with so-called Super Balls or bouncy balls. An example is the determination of gravity g in an experiment. The basic idea behind this was described by Pape1 and Sprockhoff2: The initial and final heights and the complete duration of all the bounces are measured for a certain number of bounces by the ball. On the basis of this data, the acceleration of gravity can be approximately calculated if air drag on the ball is neglected. However, in practice, it becomes clear that measuring the height of the last bounce in the process is problematic. The person performing the experiment either has to make a good estimation of its height or film the bounce in front of a measuring stick. The method is based on the important assumption that each of the individual bounces of the ball loses the same percentage of mechanical energy; the coefficient of restitution k therefore remains the same.