试题与答案

现要求用下列器材测量一节干电池的电动势. A、干电池E:电动势约1.5V,内阻未

题型:填空题

题目:

现要求用下列器材测量一节干电池的电动势.

A、干电池E:电动势约1.5V,内阻未知;

B、电流表mA:量程5mA,内阻为20~30Ω;

C、阻值为200Ω的定值电阻一个;

D、阻值为400Ω的定值电阻一个;

E、开关两个,导线若干.

①某同学设计了图甲所示的电路,在该电路中R应选择阻值为______Ω的定值电阻.

②请在图乙中按图甲的电路图完成实物连接.

③该同学在实验中,闭合开关S1、S2时,电流表的示数为I1;闭合开关S1、断开开关S2时,电流表的示数为I2.请写出用已知量和测得量表示的待测干电池的电动势E=______.

答案:

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题型:阅读理解

In the late nineteenth century, ^5,000 pianos were sold in the United States each year and, with over half a million youths learning to play the instrument, there was a huge demand for sheet music (活页乐谱).Indeed the demand was so huge that publishers rushed to enter the profitable market.During the last fifteen years of the century, many publishers began to set up shops in New York, the center for the production of the musical arts

By the turn of the nineteenth century many important publishers had their offices on 28th Street between Broadway and 5th Avenue, and this Is the area that became known as Tin Pan Alley.It was here that publishers adopted new, aggressive business practices and marketing techniques to achieve great sales.

How it became to be known by that name is unclear, but the general opinion is that it is down to a visiting journalist by the name of Monroe Rosenfeld.He described the area as being drowned in the noise coming from the producers' offices, sounding as though hundreds of people were hitting tin pans(锡锅).He used it several times in his newspaper articles in the early twentieth century and the term stuck.With time this name was popularly embraced and many years later it came to describe the U.S.music publishing industry in general.

The start of Tin Pan Alley is usually dated to about 1885,.but the end of Tin Pan Alley is less clear-cut .Some date it to the start of the Great.Depression in the 1930s when the phonograph(留声机) and radio replaced sheet music, as the driving force of American popular music, while others consider Tin Pan Alley to have continued into thel950s when earlier styles of American popular music were upstaged (抢风头) by the rise of rock & roll.

There's a plaque(纪念匾牌)on the sidewalk on 28th Street in honor of the influence of Tin Pan Alley on American popular culture, but the buildings that were home to the legendary Tin Pan Alley publishers and songwriters are up for sale and may be torn down to make room for modern high-rise buildings.

小题1:What.is the passage mainly about ?                     

A.American popular music.

B.Tin Pan Alley's future。

C.American music Industry.

D.The history of Tin Pan Alley.小题2:In the early 20th century.Tin Pan Alley was used to refer to ____.

A.the American popular culture.

B.the American printing media

C.the American rock-music center

D.the American music publishing industry.小题3:In the nineteenth century, the driving force of American popular music was:____.

A.rock & roll

B.sheet music

C.country music

D.phonographs and radios小题4:When visiting Tin Pan Alley , Rosenfeld probably felt it was ____.

A.very noisy

B.very quiet

C.wide

D.narrow小题5:We can learn from the passage that ______.

A.the term " Tin Pan Alley" was perhaps first used by Rosenfeld.

B.the old shops of Tin Pan Alley will be well protected.

C.Tin Pan Alley got its name in the early nineteenth century.

D.there were once some factories in Tin Pan Alley

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