在离地面200m高处,以初速度v0竖直上抛一个小球,9s后小球的速率为2v0,g

题型:填空题

问题:

在离地面200m高处,以初速度v0竖直上抛一个小球,9s后小球的速率为2v0,g=10m/s2,则可知v0=______m/s;再经过时间______s后小球落回地面.

考点:竖直上抛运动
题型:填空题

单句改错

       假定英语课上老师要求同桌之间交换修改作文,请你修改你同桌写的以下作文。文中共有10处语言错误,每句中最多有两处。错误涉及一个单词的增加、删除或修改。

增加:在缺词处加一个漏字符号(∧),并在其下面写出该加的词。

删除:把多余的词用斜线划掉。

修改:在错的词下面划一横线,并在该词下面写出修改后的词。

注意:1. 每处错误及其修改均仅限一词;

            2. 只允许修改10处,多者(从第11处起)不计分。

     Today was my birthday. Yesterday our English teacher told us that we were going to have a

English exam this morning, but I got up early and went over my lessons. During the exams, I carefully

finished my paper. When I got back to home in the evening, Mother was waiting me. With a new

dictionary in his hand, she patted me on the shoulder and told me to studying even harder in the future.  

Father bought me a ten-speed bicycle. How happily I was!  I made up my mind to be one of the top

student in my class.

                                                                                                                                                        

题型:填空题

感应式电能表轻载调整时,表慢调不快可能是()。

A.计度器与蜗杆啮合太深

B.磁钢间有杂物

C.上下轴承质量不合格

D.以上都可能

题型:填空题

小儿暑温的好发月份是

A.5~7月

B.6~8月

C.7~9月

D.8~10月

E.9~11月

题型:填空题

回族人在外出时严禁()。

A.露顶

B.露颈

C.露脸

D.露手

题型:填空题

支气管哮喘发作的主要病理基础是()

A.细菌感染

B.支气管痉挛

C.副交感神经兴奋

D.支气管分泌物增多

E.气道的非特异性炎症

更多题库