打点计时器实验数据记录及处理

单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,实验：探究小车速度随时间变化的规律,物理实验类型：测量型、探究型、验证型,CLOSE,CLOSE,实验数据记录及处理,一、实验过程注意事项：,1,安装时，打点计时器限位孔、长木板、小车中心轴与滑轮在同一直线上,2,释放前小车应靠近打点计时器,3,实验时先开启电源，待打点计时器工作稳定后再释放纸带,4,打好纸带后，应立即关闭电源,CLOSE,二、纸带处理,1选择纸带,2选择测量点（7个）,每5个点取一计数点(测量点),3测量各点距0的距离,目的：减小测量时的实验误差,0,1,2,3,4,5,6,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,cm,4计算相邻测量点间距，计算,x,和,t,5求各测量点的速度,v,CLOSE,二、纸带处理,1选择纸带,2选择测量点（7个）,每5个点取一计数点(测量点),3测量各点距0的距离,目的：减小测量时的实验误差,0,1,2,3,4,5,6,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,cm,1.90,4.55,8.10,12.45,17.45,23.30,1.90,2.65,3.55,4.35,5.00,5.85,位置,0,1,2,3,4,5,6,时间t/s,0,0.1,0.2,0.3,0.4,0.5,0.6,x,/10,-2,m,t,/s,速度,v,/m,s,-1,0,CLOSE,二、纸带处理,1选择纸带,3测量各点距0的距离,目的：减小测量时的实验误差,5求各测量点的速度,v,6画,v-t,图象,7从,v-t,图象求加速度,方法:,0,1,2,3,4,5,6,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,cm,1.90,4.55,8.10,12.45,17.45,23.30,1.90,2.65,3.55,4.35,5.00,5.85,4计算相邻测量点间距，计算,x,和,t,2选择测量点（7个）,每5个点取一计数点(测量点),CLOSE,t,/s,v,/(m,s,-1,),0.1,0.2,0.3,0.4,0.5,0.6,O,0.1,0.2,0.3,0.4,0.5,0.6,位置,0,1,2,3,4,5,6,时间t/s,0,0.1,0.2,0.3,0.4,0.5,0.6,速度,v,/m,s,-1,0.23,0.31,0.40,0.47,0.54,CLOSE,画图线技巧：,*,让图线尽可能通过实验点；,*,不在图线上的点尽可能均匀分布在图线两侧；,*,个别偏差太远的点可以舍去。,例：,下表为某次实验中小车在外力作用下作直线运动，在不同时刻对应的速度。试作出小车运动的,v-t,图线。,t/,s 0.14 0.20 0.26 0.32 0.38 0.44 0.50 0.56,v/,ms,-1,0.31 0.29 0.27 0.23 0.20 0.17 0.14 0.11,0,v,/,m,s,-1,t/,s,0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.1,0.2,0.3,0.4,0.5,CLOSE,t,/s,v,/(m,s,-1,),5,10,15,20,25,30,O,5,10,15,20,25,30,时间t/s,0,5,10,15,20,25,30,速度,v,/m,s,-1,15.0,16.4,18.1,19.4,21.1,22.5,23.9,课本P33第1题:,t,/s,v/,ms,-1,0,1,2,3,4,5,6,0.1,0.2,0.3,0.4,0.5,0.6,剪下的纸带表示01s内的位移大小,x,，而,v,x,，,纸带长度可表示速度大小。,1cm长的纸带代表速度大小为0.1m/s,0,1,2,3,4,5,6,课本P33第3题:,CLOSE,小结：纸带处理步骤,1选择纸带,2选择测量点（7个）,每5个点取一计数点(测量点),3测量各点距0的距离,目的：减小测量时的实验误差,5求各测量点的速度,v,6画,v-t,图象,7从,v-t,图象求加速度,方法:,4计算相邻测量点间距，计算,x,和,t,频闪照相法,若每隔0.1s闪光一次,能求出物体下落的加速度吗?,OPEN,