试题与答案

如图所示,一个质量为m的物体(可视为质点)以某一速度从A点冲上倾角为30°的固定

题型:选择题

题目:

如图所示,一个质量为m的物体(可视为质点)以某一速度从A点冲上倾角为30°的固定斜面,其运动的加速度为3g/4,这物体在斜面上上升的最大高度为h,则在这个过程中物体的

[ ]

A.整个过程中物体机械能守恒

B.重力势能增加了3mgh/4

C.动能损失了3mgh/2

D.机械能损失了mgh/4

答案:

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题型:阅读理解

In its latest move to fight online piracy (盗版), the State Administration of Radio, Film and Television (SARFT) has shut down hundreds of BT file-sharing websites, including the popular BTChina.net.

The name BT is short for Bit Torrent, one of the most common download methods used in China.As a result of sharing, the more people download the same thing, the faster the downloads get.Users can share software, music, movies, and digital books, TV dramas and pirated DVDs and CDs.

These BT sites were shut down either for operating without a license, or for breaking copyright law.The shutdown might have an immediate effect on the amount of downloads, but over time it will recover quickly, according to Aaron D.Hurvitz, a member of China’s intellectual property (知识产权) law firms.Netizens (网民) are beginning to search for new download sites.“The problem is, if you shut down the top two Bit-torrent sites, then people will simply go to number three, number four or number five on the list,” Hurvitz said.

Whether netizens like it or not, SARFT said the closed sites will have to solve the “copyright problem” if they want to reopen.Copyright should be protected.If you don’t pay for movies, investors lose money.Then no one will make movies in the future, experts say.

In the future, some experts say, the concept of “downloading” will disappear.You may not have to bother downloading content to your computer, but just enjoy it online.However, the concept of “copyright” will still be there, inspiring talented people to create new things, in which they take pride, and from which they make money.

60.Which of the following statements is TRUE?

A.Some sharing websites were shut down for lack of licenses.

B.Those closed websites will never be reopened.

C.The speed must slow down if many people download the same thing.

D.People won’t be able to enjoy content online in the future.

61.Through BT users CAN share ________.

A.movies and hardware      B.e-books and TV dramas

C.computer parts and music       D.copyright and pirated CDs

62.The author quoted Hurvitz’s words in Paragraph 3 to tell us ________.

A.there are several choices to download resources

B.how to find other ways to download resources

C.the shutdown can’t solve the copyright problem completely

D.there will be more problems for users’ downloading

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