题干

下列说法不正确的是(   )

A:火车鸣笛向我们驶来时,我们听到的笛声频率将比声源发声的频率高

B:当水波通过障碍物时,若障碍的尺寸与波长差不多,或比波长小时,将发生明显的衍射现象

C:弹簧振子从平衡位置向最大位移处运动的过程中,振子做匀减速运动

D:用两束单色光A、B,分别在同一套装置上做干涉实验,若A光的条纹间距比B光的大,则说明A光波长大于B光波长

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C

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    A few days ago, I ran into (撞上) a stranger as he passed by. I said sorry to him, and he said, “Excuse me too, I wasn’t even watching for you.” We were very polite, this stranger and I. Then we went on our way after saying goodbye.

    Later in the kitchen at home, as I cooked our meal, my daughter Betty walked up to me, very quietly. When I turned around (转身), I nearly knocked her down. “Get out of the way!” I shouted angrily. She ran away, crying.

    That night, when I lay in bed, my husband said to me, “You were so rude to Betty. Go and look around on the kitchen floor, and you'll find some flowers there. Betty brought those for you. She picked them herself ¾ pink, yellow, and your favorite blue.”

    When I heard this, I thought deeply: “While meeting with a stranger, I was calm and polite; but with my daughter, I was not patient (耐心的). I felt sad and tears began to fall.

    I quietly went to Betty's bed, “Wake up, my dear,” I said, “Are these the flowers you picked for me?” She smiled, “I found them by the tree. I knew you'd like them, especially the blue.” I said, “I am so sorry that I treated (对待) you that way today.” And she whispered (悄声说), “Mommy, that's okay ¾ I still love you anyway.” I kissed her and said, “I love you too and I do love the flowers.”

    That day Betty gave me a lesson on how to get along with each other in the family. I spent much time on work before and didn't realize how important family life was. I decided to do better in the future.