某同学在“用打点计时器测速度”的实验中，用打点计时器记录了被小车拖动的纸带的运动情况，在纸带上确定出A，B，C...

问题详情：

某同学在“用打点计时器测速度”的实验中，用打点计时器记录了被小车拖动的纸带的运动情况，在纸带上确定出A，B，C，D，E，F，G共7个计数点.相邻计数点间的距离如图所示，每两个相邻的计数点之间的时间间隔为0.10 s.(本题计算结果均保留3位有效数字)

(1) 在实验中，使用打点计时器时应先            (选填“释放纸带”或“接通电源”).

(2) 每两个计数点间还有          个点没有标出.

(3) 试根据纸带上各个计数点间的距离，每隔0.10 s测一次速度，计算出打下D点时小车的瞬时速度，并将各个速度值填入下表.

(4)将B、C、D、E、F各个时刻的瞬时速度标在直角坐标系中，并画出小车的瞬时速度随时间变化的关系图线.

【回答】

 (1)接通电源······································································································ (2分)

(2)4·········································································································· (2分)

(3)0.560··································································································· (3分)

(4)图略····································································································· (3分)

知识点：（补充）匀变速直线运动规律的应用

题型：实验,探究题