一次用闪光照相方法研究平抛运动规律时,由于某种原因,只拍到了部分方格背景及小球的3个瞬时位置A、B、C,如图所示, A、B位置在竖直方向相距3格,B、C位置在竖直方向相距5格,每格长度为5cm,则小球做平抛运动过程中从A到B的时间为 s,小球做平抛运动的初速度大小为 m/s,小球经B点时的竖直分速度大小为 m/s。(g=10m/s2)
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
一次用闪光照相方法研究平抛运动规律时,由于某种原因,只拍到了部分方格背景及小球的3个瞬时位置A、B、C,如图所示, A、B位置在竖直方向相距3格,B、C位置在竖直方向相距5格,每格长度为5cm,则小球做平抛运动过程中从A到B的时间为 s,小球做平抛运动的初速度大小为 m/s,小球经B点时的竖直分速度大小为 m/s。(g=10m/s2)
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|