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问题 计算题

如图所示，在光滑绝缘的水平轨道上方同时存在着水平向右的匀强电场和垂直纸面向里的匀强磁场，磁场的磁感应强度B＝0.1T。一质量m=1.0×10-2 kg、带电量q＝+1.0×10-2 C可视为质点的物块，从轨道上的M点无初速度释放，当该物块沿直线运动到达轨道上的N点时，恰好对轨道无压力，求此时速度多大？（g＝10m/s2）

答案

100m/s

阅读理解

A new Long March（长征）

Twenty-one people from Hong Kong and the Chinese mainland began a new Long March on October 15. They will walk about 8，000 kilometers from Ruijin， Jiangxi to Wuqi， Shanxi. They hope to get 20.2 million Yuan to build 101 schools and help poor children go back to school. They hope to finish the march by August 16, 2012.

The football team

The Chinese under-17 football team is No. 1 in Asia. They won the Asian U-17 Championship（亚洲U-17锦标赛）in Japan on Saturday. They beat the Democratic People’s Republic of Korea（朝鲜）by 1:0. After 85 minutes， Wang Weilong got the only goal. They took the cup for the first time in 12 years.

Liu leaves China

Chinese actor Liu Ye left for the US on Monday to make a film called Meteor（《流星》）。 He is going to act with the Hollywood film star Meryl Streep. His former classmate Zhang Ziyi sent Liu a message to encourage him. Liu was worried about his English， and worked hard on it before he left. People know him from films like last year’s “Mei Ren Cao”。

小题1:From the news，we know that the twenty-one people began a new Long March to ______.

A．travel around China

B．visit some schools

C．teach poor children

D．get some money and help poor children go back to school小题2:The second piece of news tells us ______.

A．Korea held this contest

B．the Chinese football team is No. 1 in South-East Asia

C．the Chinese under-17 football team won the world championship

D．the Chinese under-17 football team won the championship for the first time in 12years小题3:Which of the paragraphs is about sports？ ______

A．The 1st

B．The 2nd

C．The 3rd

D．The 3th and the 1st
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单项选择题

汽车尾气是一种危害性很大的物质。（）

A.正确

B.错误
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