题干

如图是在实验中得到的一条较为理想的纸带.把开头几个模糊不清的点去掉,以较清晰的某一个点作为计数点1,随后连续的几个点依次标记为点2、3、4.测量出各点间的距离已标在纸带上,己知打点计时器的打点周期为O.02s.打出点2时纸带的瞬时速度为____ m/s,纸带运动的加速度的值约为____ m/s2.(结果保留3位有效数字)

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0.385,9.50

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    On a rainy night three years ago my dear mom went to accompany her Lord. She did it her way.

    I got the call at work, and l headed home quickly. Mom and Dad lived on a small farm that they had owned since I was seven. I hated going there every weekend. There was nothing for a young girl to do but watch the one station on the old TV set, if the weather allowed reception.

    My mom, on the other hand, loved the peace and quiet of the land. The place was rural, with no indoor plumbing or heat. We had a big wood stove in the kitchen that did its best to heat the little farmhouse, but it always seemed cold and too quiet to me.

    In the evenings, my mom and I would sit for hours singing in the little kitchen. I sang the melody and Mom harmonized. Her favorite song was “Moon River” and we sang it over and over. Mom told me stories about how when I was a little girl I could sing before I could talk.

    As time passed, I had my own children and went to visit them every week or two. The kids loved the farm and the tractor rides with my dad. Me, well, I still hated the silence of the farm. While my mom loved to sit at her kitchen table and look out at her garden and flowers and retell all the old stories, I missed the hustle and bustle of my life at home. But I sat there listening quietly as she reminisced.

    Now, I sat back in the silence and the silence was deathly so I finally leaned over to turn on an old radio. Music always comforted me. My heart skipped a beat. “Moon River” was playing on the radio. I sat there wordless, with a tear running down my cheek, as I listened to every familiar note.