题干

在用电火花计时器(或电磁打点计时器)研究匀变速直线运动的实验中,某同学打出了一条纸带,已知计时器打点的时间间隔为0.02s,他按打点先后顺序每5个点取1个计数点,得到了O、A、B、C、D等几个计数点,如图所示,则相邻两个计数点之间的时间间隔为____s.用刻度尺量得OA=1.50cm,AB=1.90cm,BC=2.30cm,CD=2.70cm.由此可知,纸带做____运动(选填“匀加速”或“匀减速”),打C点时纸带的速度大小为____m/s.

上一题 下一题 0.0难度 选择题 更新时间:2011-04-07 03:31:58

答案(点此获取答案解析)

0.1,匀加速,0.25

同类题3

根据短文内容, 从短文后的选项中选出能填入空白处的最佳选项,选项中有两项为多余选项。

Tips for Cooking on a Tight Schedule

    From my experience, there are three main reasons why people don't cook more often: ability, money and time. ____ Money is a topic I'll save for another day. So today I want to give you some wisdom about how to make the most of the time you spend in the kitchen. Here are three tips for great cooking on a tight schedule:

    1). Think ahead. The moments when I think cooking is a pain are when I'm already hungry and there's nothing ready to eat. So think ahead of the coming week. When will you have time to cook? Do you have the right materials already? ____

    2). Make your time worth it. When you do find time to cook a meal, make the most of it and save yourself time later on. Are you making one loaf of bread? ____ It takes around the same amount of time to make more of something. So save yourself the effort for a future meal.

    3).  ____ This may surprise you, but one of the best tools for making cooking worth your time is experimentation. It gives you the chance to hit upon new ideas and recipes that can work well with your appetite and schedule. The more you learn and the more you try, the more ability you have to take control of your food and your schedule.

    Hopefully that gives a good start. ____ And don't let a busy schedule discourage you from making some great changes in the way you eat and live!

A. Try new things.

B. Ability is easily improved.

C. Make three or four instead.

D. Understand your food better.

E. Cooking is a burden for many people.

F. Let cooking and living simply be a joy rather than a burden.

G. A little time planning ahead can save a lot of work later on.