搜题请搜索小程序“爱下问搜题”
问题 问答题

小球从斜面的顶端以初速度v0=2m/s，加速度a=2m/s2沿斜面向下匀加速滑行，在到达斜面底端前一秒内所通过的位移是斜面长的

7
15
，求：

（1）斜面的长度？

（2）小球到达斜面底端的速度大小？

答案

（1）设整个过程中的运动时间为t，则v0t+

1
2
at2-[v0(t-1)+
1
2
a(t-1)2]=
7
15
(v0t+
1
2
at2)

解得t=3s．

则斜面的长度L=v0t+

1
2
at2=2×3+
1
2
×2×9m=15m．

（2）小球达到底端的速度v=v0+at=8m/s．

答：（1）斜面的长度为15m．

（2）小球达到斜面底端的速度大小为8m/s．

改错题
短文改错。
     此题要求改正所给短文中的错误，对标有题号的每一题做出判断：
     如有错误（每行只有一个错误），则按下面情况改正：
     此行多一词：把多余的词用斜线（＼）划掉，在该行右边横线上写出该词，并也用斜线划掉。
     此行缺一词：在缺词处加一个漏字符号（^），在该行右边横线上写出该加的词。
     此行错一词：在错词的下面划一横线，在该行右边横线上写出改正后的词。
     注意：原文没有错误不要改。
     Did you enjoy yourself yesterday? I suppose you do. But I'd
like to tell you what a bad day I had yesterday. Nothing
just went wrong. On the morning, my alarm clock didn't ring,
since I woke up an hour late. I was in such a hurry that I burnt my
hand when I was cooking the breakfast. Then I ran out of the house
to catch the 8:30 buses. This is the bus I usually take. But, you
may laugh, I missed it of course. I am very unhappy, and scared
as well because teacher hates the students coming late to school.
So I ran three miles to school only to discover that anybody
was there. The school was quiet but peaceful. Our classroom was
locked. I realized that moment. It was Sunday. 		1. _____
2. _____
3. _____
4. _____
5. _____
6. _____
7. _____
8. _____
9. _____
10. _____
查看答案
单项选择题

根据我国检察官法有关任职回避的规定，下列表述哪一项是不正确的( )

A．杨某和蒋某系夫妻，二人不得同时在同一人民检察院部门担任检察员和助理检察员
B．何甲和何乙系姐弟，二人不得同时在同一人民检察院起诉科担任助理检察员
C．检察官袁某从人民检察院离任后2年内，不得担任诉讼代理人或者辩护人
D．林某为县人民检察院检察官，其子小林不得担任该县人民检察院办理案件的辩护人
查看答案