问题
计算题
在距离斜坡底端10 m的山坡上，一辆小车以4m/s的速度匀速向上行驶5s后，小车又以2m/s的速度匀速向下行驶，设位移和运动方向都以沿斜坡向下为正方向，试作出小车20 s内的x-t图象和v-t图象，由图象再确定小车在20 s末的位置。
答案
解：x-t图象如图甲，v-t图象如图乙，20 s末小车在斜坡底端处
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在距离斜坡底端10 m的山坡上，一辆小车以4m/s的速度匀速向上行驶5s后，小车又以2m/s的速度匀速向下行驶，设位移和运动方向都以沿斜坡向下为正方向，试作出小车20 s内的x-t图象和v-t图象，由图象再确定小车在20 s末的位置。
解：x-t图象如图甲，v-t图象如图乙，20 s末小车在斜坡底端处
任务型阅读 （共10小题，每小题1分，满分10分） 认真阅读下列短文，并根据所读内容在文章后表格中的横线上填入最恰当的单词。 注意：每空只填一个单词。 Maybe you are an average student. You probably think you will never be a top student. This is not necessary so, however. Anyone can become a better student if he or she wants to. Here is how. 1). Plan your time carefully. When you plan your week, you should make a list of things that you can have to do. After making the list, you should make a schedule of your time. First time for eating, sleeping, dressing, etc. Then decide a good, regular time for studying. Don’t forget to set aside enough time fro entertainment. A weekly schedule may not solve all your problems, but it will force you to realize what is happening to your time. 2). Find a good place to study. Look around the house for a good study area. Keep this space, which may be a desk or simply a corner of your room. Free from everything but study materials. No games, radios, or television. When you sit down to study, concentrate on the subject. 3). Make good use of your time in class. Take advantage of class time to listen to everything the teachers say. Really listening in class means less work later. Taking notes will help you remember what your teachers say. 4). Study regularly. When you get home from school, go over your notes. Review the important points that your teachers mentioned in class. If you want to know what your teacher is going to discuss the next day, read the material in advance. This will help you understand the next class. If you do these things regularly, the material will become more meaningful, and you will remember it longer. 5). Develop a good attitude about tests. The purpose of a test is to show what you have learned about a subject. They help you remember your new knowledge. The world won’t end if you don’t pass a test, so don’t be overly worried. There are other methods that might help you with your studying. You will probably discover many others after you have tried these. How to Become a Better Student?
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