题干

如图甲所示,小明用弹簧测力计拉木块,使它沿水平木板匀速直线滑动,图乙是他两次拉动同一木块得到的距离随时间变化的图像。下列说法正确的是(   )

A:木块第一次受到的拉力较大

B:拉力第一次做的功多

C:拉力第一次做功的功率大

D:两次拉力做的功一样多

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答案(点此获取答案解析)

C

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完形填空

    Diane Ray was completely self-centered and very spoilt. Her parents gave her1she wanted, knowing that she would throw a temper tantrum(耍小孩脾气)if they did not. She would scream and kick and2on the floor drumming her heels. Her parents always3.

    That was why she was alone on the4, wearing an expensive swimsuit. It has taken a massive tantrum to5her parents to buy it. They were back at the beach-house,6from the tantrum she had thrown when they told her that it was too dangerous to go diving7. “Dangerous?” she had said. “You just don't want me to have8. I'm going and if you try to stop me, I'll scream.”

    “What are you doing ?” a voice asked. Diane jumped. She did not know that the man was there9  he spoke .

    “I'm going diving, ” she answered.

    “You shouldn't swim that day, ” the man10. “There is a storm coming up.”

    “You should mind your own11!” Diane replied and walked into the gentle waves.

    “If you go out there you'll be12,” the man called after her. She did not bother to reply.

    Diane slipped into the water and dived13until white caps began rolling in and it became harder to14against the current (水流). Saltwater hit against her face, making it15to breathe. Oh, why had she not listened to advice.

    Panicking, she began to16. Then, just as it seemed as if she would slip beneath the surface, she heard a17voice. “Hold on ! I'm coming.” With18, she saw the old man rowing an ancient-looking boat towards her. “I hope you've learned a lesson. You put us both in19, ” he shouted angrily, as he dragged her over the side of the20. Gratefully, Diane thanked him and ran towards the beach-house.