问题 问答题 简答题

调偏托辊的调偏原理是什么?

答案

参考答案:

当皮带跑偏时,输送带的边缘与悬置于回转架的立辊接触,当立辊受到皮带边缘的作用力后,它给回转施加回转力臂,使回转架转过一定的角度从而达到调偏作用。

单项选择题
阅读理解

Country music is one of the most popular kinds of music in the United States today because it is about simple but strong human feelings and events-love, sadness, good times, and bad times. It tells real-life, stories and sounds the way people really talk. As life becomes more complicated(复杂), it is good to hear music about ordinary people.

Country music, sometimes called country-western, comes from two kinds of music. One is the traditional music of the people in the Appalachian Mountains in the eastern Unite States. The other is traditional cowboy music from the west. The singers usually play guitars, and in the 1920s they started using electric guitars. At first city people said country music was low class. It was popular mostly in the South. But during World War II, thousands of Southerners went to the Northeast and Midwest to work in the factories. They took their music with them. Soldiers from the rest of the country went to army camps(军营)in the South. They learned country music. Slowly it became popular all over the country.

Today country music is also popular everywhere in the United States and Canada—in small towns and in New York City, among black and white, and among educated and uneducated people. About 1, 200 radio stations broadcast country music twenty-four hours a day. English stars sing it in British English, and people in other countries sing it in their own languages. The music that started with cowboys and poor southerners is now popular all over the world.

57. It can be learned from the passage that country music comes from_________-

A. the Northeast and Midwest

B. factories and army camps in the South

C. the Appalachian Mountains and the West

D. real-life stories in small towns

58. Before World War II country music was popular mainly in________.

A. the south           B. the north

C. the Midwest        D. the Northeast

59. During World War II many Southerners went to the Northeast and the Mid-west because____.

A. they wanted to take music with them

B. they wanted to make other people like country music

C. they wanted to work in the factories there

D. they wanted to make country music popular

60. Which of the following is NOT true according to the passage?       

A. Country music is about human feelings and events.

B. Country music is sung by stars all in English.

C. Country music is popular among city people today.

D. City people didn’t like country music at first.