问题 选择题

如图表示两个相干波源S1、S2产生的波在同一种均匀介质中相遇.图中实线表示某时刻的波峰,虚线表示的是波谷,下列说法正确的(  ).

A.a、c两点的振动加强,b、d两点的振动减弱

B.e、f两点的振动介于加强点和减弱点之间

C.经适当的时间后,加强点和减弱点的位置互换

D.经半个周期后,原来位于波峰的点将位于波谷,原来位于波谷的点将位于波峰

答案

AD

a点是波谷和波谷相遇的点,c是波峰和波峰相遇的点,都是振动加强的点,而b、d两点都是波峰和波谷相遇的点,都是振动减弱的点,A正确;e位于加强点的连线上,仍为加强点,f位于减弱点的连线上,仍为减弱点,B错误;相干波源叠加产生的干涉是稳定的,不会随时间变化,C错误;因形成干涉图样的介质质点也是不停地做周期性振动,经半个周期步调相反,D正确.

单项选择题
阅读理解

阅读理解。

     People from East Asia tend to have more difficulty than those from Europe in distinguishing facial

expressions-and a new report published online in Current Biology explains why.

       Rachael Jack,University of Glasgow researcher,said that rather than scanning evenly (均匀的) 

 across a face asWestemers do,Eastemers fix their attention on the eyes.

     "We show that Eastemers and Westemers look at different face features to read facial expressions,

" Jack said." Westemers look at the eyes and the mouth in equal measure.whereas Easterners favor the

eyes and neglect(忽略) the mouth. "

      According to Jack and her colleagues,the discovery shows that human communication of emotion is

more complex than previously believed. As a result,facial expressions that had been considered

universally recognizable cannot be used to reliably convey emotion in cross-cultural situations.

       The researchers studied cultural differences in the recognition of facial expressions by recording the

eye movements of 13 Westem Caucasian and 13 East Asian people while they observed pictures of

expressive faces and put them into categories: happy,sad,surprised,fearful,disgusted,angry,or neutral.

They compared how accurately participants read those facial expressions using their particular eye

movement strategies.

     It turned out that Eastemers focused much greater attention on the eyes and made significantly more

errors than Westerners did.  "The cultural difference in eye movements that they show is probably a

reflection of cultural difference in facial expressions,"Jack said." Our data suggest that whereas

Westemers use the whole face to convey emotion, Eastemers use the eyes more and mouth less."

       In short,the data show that facial expressions are not universal signals of human emotion.  From

here on,examining how cultural factors have diversified these basic social skills will help our understanding of human emotion.  Otherwise, when it comes to communicating emotions across cultures, Eastemers and Westemers will find themselves lost in trans- lation.

1. The discovery shows that Westemers _______.   

A. pay equal attention to the eyes and the mouth

B. consider facial expressions universally reliable

C. observe the eyes and the mouth in different ways

D. have more difficulty in recognizing facial expressions

2. What were the people asked to do in the study?            

A. To make a face at each other.                

B. To get their faces impressive.

C. To classify some face pictures.              

D. To observe the researchers' faces.

3. What does the underlined word "they" in Paragraph 6 refer to?   

A. The participants in the study.

B. The researchers of the study.

C. The errors made'during the study.

D. The data collected from the study.

4.  In comparison with Westemers,Eastemers are likely to _______ 

A. do translation more successfully

B. study the mouth more frequently

C. examine the eyes more attentively

D. read facial expressions more correctly

5. What can be the best title for the passage?  

A. The Eye as the Window to the Soul.

B. Cultural Differences in Reading Emotions.

C. Effective Methods to Develop Social Skills.

D. How to Increase Cross-cultural Understanding.