如图所示为一皮带传动装置,右轮的半径为r,a是它边缘上的一点,左侧是一轮轴,大轮

题型:不定项选择

问题:

如图所示为一皮带传动装置,右轮的半径为r,a是它边缘上的一点,左侧是一轮轴,大轮半径为4r,小轮半径为2r,b点在小轮上,到小轮中心距离为r,c点和d点分别位于小轮和大轮的边缘上,若在传动过程中,皮带不打滑,则

[ ]

A.a点与b点线速度大小相等

B.a点与c点角速度大小相等

C.a点与d点向心加速度大小相等

D.a、b、c、d四点,加速度最小的是b点

考点:线速度角速度向心加速度
题型:不定项选择

阅读理解:阅读短文,完成后面5个小题,正确的“T”用表示,错误的用表示“F”。

       A water-saving campaign was started among school children in Beijing to spread the message of

Green Olympic.

       "Which seasons see more precipitation (江水) in Beijing?" "Summer and winter."

       This was a simple conversation between Zhou Youhong-a member of the Beijing Olympic Green

Action Promotion Group (北京奥运会绿色行动宣传团) and some school kids during Zhou's speech

on environmental protection.

       The interesting activity carded the message that is trying to tell the future generations (几代人) as

they jointly launched (发起) a water-saving campaign among the kids.

       As a part of the plan to promote "Green Olympics", the campaign called on students of over 1,000

primary schools in the city to take part in it this year.

       During the launch ceremony of the campaign, the students were given water-saving materials. They

posted water-saving tips at every comer of the school to remind other people to cherish (珍惜) the water

resources.

       Students were encouraged to bring the message to their family members and show their feedback

(反馈) on schools' blackboards.

       "We hope that through this campaign, the young people will increase the awareness (意识) of

environmental protection," said Xu Xiaoxuan, director of BOCOG (北京奥组委) Environmental

Activity Dept. "Such practice is of great meaning not only for the kids, but also for every member o2"

the society," he continued.    

( )1. Zhou Youhong was a member of the Beijing Olympic Green Action Promotion Group.

( )2. The campaign called on all the people in the city to take part in it.    

( )3. Students can show their feedback on schools' blackboards.     

( )4. The campaign was of great meaning only for the kids.                

( )5. The main idea of this passage is to let children learn to save water.    

题型:不定项选择

病毒性脑炎的临床特征不包括()

A.多为急性或亚急性起病,部分患者有前驱症状

B.以单纯疱疹病毒性脑炎最为常见

C.一般散发,无季节性与区域性,可见于任何年龄组

D.精神症状可为首发症状也可为主要临床表现

E.仅少数病情严重的患者出现意识障碍

题型:不定项选择

光照:影子

A.振动:声音

B.飓风:损失

C.努力:成功

D.酒精:气氛

题型:不定项选择

风湿性心脏病心房颤动病人突然抽搐、偏瘫,首先考虑()。

A.心力衰竭加重

B.洋地黄中毒

C.低钾血症

D.脑栓塞

E.蛛网膜下腔出血

题型:不定项选择

对卖淫、嫖娼和引诱、容留、介绍他人卖淫违反治安管理行为,可以适用当场处罚。()

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