题干

从某一高度相隔1s先后释放两个相同的小球甲和乙,不计空气阻力,它们在空中任一时刻(   )

A:甲乙两球距离始终保持不变,甲乙两球速度之差保持不变

B:甲乙两球距离越来越大,甲乙两球速度之差也越来越大

C:甲乙两球距离越来越大,甲乙两球速度之差保持不变

D:甲乙两球距离越来越小,甲乙两球速度之差也越来越小

上一题 下一题 0.0难度 选择题 更新时间:2016-04-08 10:34:07

答案(点此获取答案解析)

C

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信息归纳:阅读下文,根据所提供的信息,完成下列表格。

    Your Junior 3 year will finish soon. Do you want to say something about your junior school life? What were the rewards (收获) of the three years? Our readers have their stories to share.

Ben,15,Guangzhou,Guangdong

   I experienced a hard time in Junior 2 when my grades suddenly dropped(下降) a lot. I faced great pressure. In the following summer vacation, I worked hard by studying for 10 hours a day. It was crazy, but when I became one of the top students again, I felt everything had been worthwhile(值得的).

Julie, 13,Beijing

     In July, 2011,I had a trip to the UK with some students and teachers. When we arrived there, the other students and I didn't want to eat the local food. The teachers were worried and tried to make us eat. When we finally finished the meal, the guide said that the world now sees how spoiled(被宠坏的)Chinese kids are. I felt really sorry.

John,14,Hangzhou,Zhejiang

    I lived in a dorm(寝室)during junior school. It was a great challenge since I had never left my parents before that. I had to take care of everything myself. I learned to make my bed and get along with roommates. I also learned to make a schedule to arrange(安排)my time .I've done a good job and I feel proud.


Information Card

Age of Ben

____

Place John is from

____

Time Julie went to the UK

____

How Ben improve his grades

____

Things John has learned during junior school

Make the bed ____

Make a schedule to arrange time