问题 选择题

掉在水平地面上的弹性小球会跳起,而且弹跳的高度会越来越低。图示是小球弹跳的频闪照片,小球在1,2位置的高度一样。下面说法正确的是(   )

A.小球在1、2位置的势能相同,机械能也相同

B.小球在1、2位置的动能相同,2位置的机械能较小

C.小球在1位置的动能较大,机械能也较大

D.小球在2位置的势能较小,机械能也较小

答案

答案:C

题目分析:小球在两个位置的高度相同,则重力势能相同,由于小球在弹跳过程中高度越来越低,所以其机械能减小,则小球在1位置的机械能较大,动能也较大。

阅读理解

阅读下面的短文,并根据短文后的要求答题(请注意问题后的字数要求)。

     JAY Chou, S.H.E. and Happy Boys? They are some of the singers who keep your music world busy.

But _____ Peking Opera? Is it only the favorite pastime of your grandfather?

     Now, you have the chance to get to know the real beauty of this traditional art. This term, a Peking

Opera project is starting in 200 schools in 10 provinces and municipalities (直辖市) .It will involve 15

works of Peking Opera, both classic and modern.

     So how much do you know about this 200-year-old art? Peking Opera combines instrumental music,

singing, dancing, acting and acrobatics (杂技). Full of Chinese cultural elements, Peking Opera presents

to the audience an encyclopedia (百科全书) of Chinese culture with unfolding stories, beautiful paintings,

wonderful costumes and graceful gestures.

     The art form has created many "firsts" in Chinese dramas:the abundance of repertoires (曲目), the n

umber of artists and opera troupes and audience. So it is called the national opera of China.

     There are five main roles in Peking Opera:sheng,dan,jing,mo and chou. Sheng is the leading male actor.

Dan is the female roles. Jing refers to male roles with colored face paintings who represent warriors (战士),

heroes, statesmen, adventurers and demons (魔鬼). Mo is a minor male role. Chou is a male comic character

with a white patch on the nose. They play roles of wit and humor. It is these characters that keep the

audience laughing to ease tension in some serious plays.

1. What is the best title of the passage? (Please answer within 10 words.)

    ______________________________________________________________________________________

2. Which sentence in the passage can be replaced by the following one? Is it only the thing that your

    grandfather likes best to kill time? 

    ______________________________________________________________________________________ 

3. Please fill in the blank with proper words or phrases to complete the sentence. (Please answer within 10

    words.) 

    ______________________________________________________________________________________ 

4. What's your opinion about the Peking Opera project started in schools? (Please answer within 30 words.)

    ______________________________________________________________________________________

5. Translate the underlined sentence into Chinese. 

    ______________________________________________________________________________________

单项选择题