题干

 如图是足球运动员踢足球时的情景,下列说法正确的是(  )

A:球被脚踢出去,说明只有球才受到力的作用

B:脚踢球使球飞出去,说明力是物体运动的原因

C:足球在空中飞行过程中,运动状态一定发生改变

D:空中飞行的足球,若它所受的力全部消失,它一定沿水平方向做匀速直线运动

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答案(点此获取答案解析)

C

同类题3

阅读下面短文,从短文后各题所给的四个选项(A、B、C、D)中,选出可以填入空白处的最佳选项。

    People from every corner flooded into the streets that Christmas Eve. “Frosty the Snowman,” and “Jingle Bells” 1 in stores; on the pavements, the street singers performed happily. Everyone, was2 by someone else, delighted and cheerful. I was alone.

    As one of 8 kids of a Brazilian family, brought up in America's crowded apartment, I'd spent several years searching for aloneness. Now, 3, at 27, a college student after the 4 with my girlfriend , every cell inside me wanted to be alone, 5 not at Christmas. My family had 6 to Brazil and my friends were 7 with their own lives. Dusk was approaching, and the fact that I had to return to my 8 home made me sad. Lights from windows blinked, and I hoped someone would 9 from one of those homes to invite me inside with a Christmas tree decorated with shiny fake snow and 10 presents.

    At a market, I felt more 11 when people were buying lots of goods, which 12 the gifts we received as children in my mind . I missed my family and wanted to cry for wanting to be alone and for having achieved it.

    Outside the church , a manger(小耶稣) had been set 13. I stood with others watching the scene, some of them 14themselves, praying. As I walked home, I realized that leaving Brazil was still a painful experience as I struggled with 15 I had become in 15 years in America. I'd mourned the 16, but for the first time, I recognized what I'd gained. I was independent, 17 and healthy. My life was still ahead, full of 18.

    Sometimes the best gift is the one that you give yourself. That Christmas, I gave myself 19 for what I'd obtained up to now and promise to go forward. It is the best gift I've ever got, the one that I most 20.