物体做曲线运动,则() A. 物体的速度大小一定变化 B. 物体的速度方向一定变化 C. 物体的加速度大小一定变化 D. 物体的加速度方向一定变化 答案:考点: 曲线运动. 分析: 物体做曲线运动的条件是物体所受合外力方向和速度方向不在同一直线上,曲线运动最基本特点是速度方向时刻变化,根据物体做曲线运动条件和曲线运动特点即可解答本题. 解答: 解:A、物体做匀速圆周运动时,速度大小不变,故A错误; B、物体做曲线运动,轨迹是
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(1)
How many American films will there be in Grand Cinema this week?
[ ]
A.
One
B.
Two
C.
Three
D.
Four
(2)
If you want to see the film Harry Porter(Ⅲ), you will pay ________.
[ ]
A.
$4.5
B.
$5
C.
$5.5
D.
$6
(3)
You are free on Saturday morning, so you can see the film ________ in Grand Cinema.
[ ]
A.
Kungfu Hustle
B.
A World Without Thieves
C.
Troy
D.
Harry Porter(Ⅲ)
(4)
Your favorite star is Zhou Xingchi, so you have to see his film at ________ on Friday.
[ ]
A.
9∶30 am
B.
4∶30 pm
C.
6∶30 pm
D.
9∶00 pm