（1）有一游标卡尺，主尺的最小分度为1mm，游标尺上有20个等分刻_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题问答题

（1）有一游标卡尺，主尺的最小分度为1mm，游标尺上有20个等分刻度，用该卡尺测长度时，可以准确到______mm，如图1所示工件的长度为______mm．

（2）做匀加速直线运动的小车，牵引一条纸带通过打点计时器，交流电源的频率为50Hz，由纸带上打出的某一点开始，每5个点剪下一段纸带，按图2所示，使每一条纸带下端与x轴重合，左边与y轴平行，将纸带段粘贴在直角坐标系中，则小车运动的加速度是______m/s²（保留两位有效数字）．

答案

（1）游标把1mm分成20格，所以可以精确到

1

20

=0.05mm，

游标卡尺的主尺读数为103mm，游标尺上第8个刻度与主尺上某一刻度对齐，故其读数为0.05×7mm=0.35mm，所以最终读数为：103mm+0.35mm=103.35mm；

（2）从图中可以看出在相邻的相等时间内的位移之差是一恒量，即△x=aT²=10×10^-3m．所以a=

△x

T2

=

0.01

0.01

=1m/s²

故答案为：（1）0.05 103.35 （2）1

单项选择题

公文处理过程中，确保公文质量的决定性环节是（）

A．深刻领会领导意图撰写公文

B．秘书部门对文稿进行认真审核

C．机关领导人对公文进行审批，签署

D．加盖机关印章，确保公文的权威与效力

完形填空

The story I’m going to tell truly happened in my life.
The other day, I met a man outside the gym who       a movie star. He was handsome and smiling. His upper body was muscular（肌肉发达的）and he       to be on top of the world.
“How are you?” I       with a smile. “I’m doing really well,” he replied in a cheerful voice. His enthusiasm and big smile        the parking garage.        as he walked up, I       his long legs were thin and I saw he had a silver cane (手杖). “Why do you need that cane?” I couldn’t        thinking he had a minor injury. “I have MS,” he answered in a        voice too, as if his broad smile       left his face. Multiple Sclerosis（多发性硬化症）is a very serious disease and often painful. I looked at him from my little red sports car and said, “You        it very well. You seem like a happy man       the MS.” Without losing a bit of his smile he replied, “I am a happy man,” and then added, “I’d be even happier if I had that sports       .”
It was ironic (讽刺的). Just       we spoke, I’d been sitting in that little sports car, feeling sad about my painful shoulder over the last 11 months as I was       after an operation. Here’s a man with a       far tougher than mine, but his positive attitude made him feel no less happiness. He went on with his       of life as usual, which moved me deeply.
It was also a wonderful reminder of that old       , “I cried because I had no shoes. Then I met a man who had no feet.”       your problems, just keep in       that none of us goes through life       and you should make the most of what you have, like the man with MS. Count your blessings.

B．talked about

C．agreed with

D．looked like

A．in spite of

B．in return for

B．disappointment