问题
选择题
| 下列关于速度的说法正确的是（ ） A．速度是描述物体位置变化的物理量 B．瞬时速度方向就是物体运动的方向 C．位移方向和速度方向一定相同 D．匀速直线运动的速度方向是可以改变的 |
答案
答案：B
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| 下列关于速度的说法正确的是（ ） A．速度是描述物体位置变化的物理量 B．瞬时速度方向就是物体运动的方向 C．位移方向和速度方向一定相同 D．匀速直线运动的速度方向是可以改变的 |
答案：B
| 阅读理解。 |
| Is your schoolbag too heavy to carry? The e-schoolbag will help you. In fact, the e-schoolbag should be called the e-textbook. It is a small computer for students. Heavy schoolbags are not good for them. But the e-schoolbag will change (改变) everything. It is light and small, but it can save all the things for study, like a textbook, an exercise book and so on. There are some chips (芯片) of textbooks for students. The students can put the right chip into the e-schoolbag and read the textbook page by page on the screen. And they can also use the e-schoolbag to take notes (做笔记) or send emails to their teachers. Some people say the e-textbook is good for students' study, but some people say it is not good for students' eyes. I think only time will tell. |
| 1. An e-schoolbag is ______. |
[ ] |
| A. a TV set B. a usual book C. a heavy bag D. a small computer |
| 2. The e-schoolbag is ______. |
[ ] |
| A. big but light B. heavy and big C. small and light D. the same as a usual schoolbag |
| 3. E-schoolbags are designed (设计) for ______. |
[ ] |
| A. managers B. students C. writers D. teachers |
| 4. The underlined word "screen" means "______" in Chinese. |
[ ] |
| A. 显示屏 B. 键盘 C. 录音机 D. 幻灯机 |
| 5. Which of the following is RIGHT? |
[ ] |
| A. All the people like the e-schoolbag. B. E-schoolbags can do everything for students. C. Students can use the e-schoolbag to read the textbook. D. The e-schoolbag is good for students' eyes. |