The sound of impacts made by the two outermost balls in a Newton’s cradle were recorded with a smartphone sound sensor. As a time series of sound pressure levels, the data made it possible to obtain the period of the identical pendulums. Hence the determination of the acceleration due to gravity. The result, on average, g = 9.99 m s⁻², is close enough to the locally accepted value of 9.78 m s⁻² for instructional purposes.

中文翻译：

---

牛顿的摇篮：使用智能手机声音传感器从撞击声中提取g

牛顿摇篮中两个最外面的球发出的撞击声是用智能手机声音传感器记录的。作为声压级的时间序列，这些数据使得获得相同钟摆的周期成为可能。因此确定重力加速度。结果，平均而言，g = 9.99 ms ^-2足够接近本地接受的值 9.78 ms ^-2用于教学目的。