关于合力对物体速度的影响，下列说法中正确的是 [ ] A．如_爱下问搜题

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问题不定项选择

关于合力对物体速度的影响，下列说法中正确的是 [ ]

A．如果合力方向总跟速度方向垂直，则物体速度大小不会改变，而物体速度方向会改变

B．如果合力方向跟速度方向之间的夹角为锐角，则物体的速度将增大，方向也发生改变

C．如果合力方向跟速度方向成钝角，则物体的速度将减小，方向也发生改变

D．如果合力方向与速度方向在同一直线上，则物体的速度方向不改变，只是速率发生变化

答案

ABC

听力题

动词填空用括号内所给动词的适当形式填空。(本大题共8分，每小题1分)

1. Travellers __________(remind) that it’s wise to take a map and an umbrella.

2. Did you notice the boy in red __________(pick) apples in that tree just now?

3. These days, the governments of China and Japan ___________(argue) about the problems of

Diaoyu Island.

4. ---Did you see him come in? ---No, I __________(watch）TV.

5. The Greens moved to Paris in 2005 and ___________(live) there ever since.

6. Miss Lv says learning English __________(require) action, or we’ll get nothing.

7. More information must be paid attention to ___________(discover) the truth.

8. If you don’t work hard, you __________ (suffer) from much stress at work sooner or later.

填空题

在肝硬化腹水治疗中，利尿不宜过猛，每周体重减轻以不超过_________为宜，一次抽腹水不宜超过_____________