Question

（1）图1游标卡尺读数为                                                                               mm．    

（2）某兴趣小组的同学利用如图2所示的实验装置，测量木块与长木板之间的动摩擦因数，图中长木板水平固定．                                                                                                                                    

①实验过程中，打点计时器应接在交流电源上，调整定滑轮的高度，使绳子拉力方向跟平板平行．                        

②已知重力加速度为g，测得木块的质量为M，                                                         

砝码盘和砝码的总质量为m，砝码盘、砝码和木块                                                    

的加速度大小为a，则木块与长木板之间的动摩擦                                                      

因数μ=                                                                                                           ．       

③实验时，某同学得到一条纸带，如图3所示，每隔三个计时点取一个计数点，记为图中0、1、2、3、4、5、6点．测得相邻两个计数点间的距离分别为s₁=0.96cm，s₂=2.88cm，s₃=4.80cm，s₄=6.72cm，s₅=8.64cm，s₆=10.56cm，打点计时器的电源频率为50Hz．计算此纸带的加速度大小a=                                                   m/s²，打计数点“4”时纸带的速度大小v=                                         m/s．（保留两位有效数字）

                          

                                                                                                                                 

Answer 1

（1）2.25；（2）②；③3.0；0.96．