题目

阅读理解 I was raised in a house where mysisters and I weren't trusted by our mother to manage our own appearance. As aresult, there were rules, and trends were largely ignored. A few years ago, Iwas home for a visit when my mom, now in her early 70s, called me into herbedroom. We were about ready to leave for dinner. “I don't know what to wear”she complained “You girls always look so good. ” I paused in the doorway and looked at her, wonderingif I'd misheard. “What do you mean?” I asked her. “You know what to wear No.”she answered. “I don't. Can you pick something?” I 如图甲所示是某同学探究加速度与力的关系的实验装置。他在气垫导轨上安装了一个光电门B，在滑块上固定一遮光条，滑块用细线绕过气垫导轨左端的定滑轮与力传感器相连(力传感器可测得细线上的拉力大小)，力传感器下方悬挂钩码，每次滑块都从A处由静止释放。(1)该同学用游标卡尺测量遮光条的宽度d，如图乙所示，则d=________mm。(2)下列不必要的一项实验要求是________。A.将气垫导轨调节水平B.使A位置与光电门间的距离适当大些C.使细线与气垫导轨平行D.使滑块质量远大于钩码和力传感器的总质量(3)实验时，将滑块从A位置由静止释放，由数字计时器读出遮光条通过光电门B的时间t，测量出滑块在A位置时遮光条到光电门B的距离L，则滑块的加速度a=________。(4)为探究滑块的加速度与力的关系，改变钩码的质量，测出对应的力传感器的示数F和遮光条通过光电门的时间t，通过描点要作出它们的线性关系图像，处理数据时纵轴为F，横轴应为________。A.t B.t2 C. D.