试题与答案

李林有一枚寿山石印章,他用天平测出其质量为78.4g,又用刻度尺测出它的长、宽、

题型:计算题

题目:

李林有一枚寿山石印章,他用天平测出其质量为78.4g,又用刻度尺测出它的长、宽、高分别为2cm、2cm、7cm。(g=10N/kg) 问:

(1)这枚印章受到的重力是多大?

(2)这枚印章的密度是多大?

(3)若把它竖直放置在水平桌面上,它对桌面的压强是多大?

答案:

解:

(1)78.4g=0.0784kg,G=mg=0.0784kg×10N/kg=0.784N

(2)V=2cm×2cm×7cm=28cm3,ρ=m/V=78.4g÷28cm=2.8g/cm3

(3)S=2cm×2cm=4cm2=4×10-4m2,P=F/S=G/S=0.784N÷(4×10-4m2)=1960Pa。 

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题型:阅读理解

In 1638, John Harvard donated some money and about four hundred books to a new university. This was the beginning of the library at Harvard University. The gift was so important that the university was named for John Harvard.

Thomas Bray began the first free lending library in the late 1600s. He set up more than 30 or these libraries in the American colonies. However, the idea for this kind of free library ended when Bray died in 1730. In 1731, Benjamin Franklin and some friends started the first subscription library in the United States. In a subscription library people pay money to become members, but they may borrow the books without paying again.

In the United States, every child had a free education. This idea soon led to free libraries. One of the first libraries that used tax money to buy books was a library in Peterborough, New Hampshire. This library was set up in 1833.

小题1:The main idea of paragraph 2 is________.

A. Franklin started the first subscription library

B. in a subscription library people pay money to become members

C. Bray and Franklin were important in the history of public libraries

D. Bray died in 1730 and Franklin died in 1833小题2:The underlined word “borrow” means_______.

A.read and write with no help from another person

B.use for a short time and then return

C.like very much

D.lend小题3:The reading does not say it, but we can guess that_______.

A.there were free schools in the United States before there were free libraries

B.free schools and free libraries in the United States began at about the same time

C.the library in New Hampshire also had a free school in it

D.there were free libraries in the United States before there were free schools小题4:Harvard University began_______.

A.in 1731

B.in 1730

C.in 1833

D.in 1638小题5:At the library that Franklin started, ________.

A.children could use books for no money at all

B.people paid a little money in the beginning but none after that

C.people paid a lot of money in the beginning but none after that

D.both A and B

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