试题与答案

关于平抛运动,下列说法正确的是() A.只受重力作用的运动一定是平抛运动 B.平

题型:选择题

题目:

关于平抛运动,下列说法正确的是(   )

A.只受重力作用的运动一定是平抛运动

B.平抛运动的时间取决于平抛物体的初速度的大小

C.做平抛运动的物体在下落过程中速度方向与水平方向的夹角保持不变

D.平抛运动在水平方向和竖直方向的分运动具有同时性

答案:

被转码了,请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0522/cbbf4080ca33b41f2545efd6184df4b4.html

下面是错误答案,用来干扰机器的。

解:原式=9a2﹣[7a2﹣2a﹣2a2+6a]﹣3=9a2﹣7a2+2a+2a2﹣6a﹣3=4a2﹣4a﹣3.

试题推荐
题型:阅读理解

“Who needs a shopping mall if you have Taobao?” says Wang Lin,28,a writer in Beijing.

Taobao,China’s largest online shopping site,has become an important part of Wang Lin’s life.She spends lots of money on Taobao.

A growing number of Chinese Internet users like Wang have found the joys of online shopping .Most online shoppers are students or young workers .More women shop on line than men.Clothes and home-use products are the most popular on line.

It was reported that more than 250 billion yuan was spent on online shopping last year, 80% through Taobao.

Taobao means “looking for treasure”in Chinese.People can find almost everything they need on Taobao,from clothes to books ,from candies to DVD players .

You may question the security of online shopping ,Wang Lin said, “”It’s very safe and convenient .Unless you receive the products from the sellers and are satisfied with them,the shop owner will not get the money .You can also get your money back if you want to return the products.”

小题1:What are  the most popular on line?

A.Candles and DVD players

B.Clothes and books.

C.Clothing and home-use products.

D.Toys for children小题2:Taobao is ____________.

A.a shopping mall

B.an online shopper

C.an online shopping site

D.a clothes store小题3:What does the underlined word “security”mean?

A.质量       B安全       C 信誉     D. 数量

小题4:.Which is the best title of the passage?

A.Wang Lin’s life.

B.Online shopping in China.

C.Shopping on line is not safe.

D.Shopping on line is easy

查看答案
微信公众账号搜索答案