问题 实验题

某同学把电压表(三只)、电流表(两只)、定值电阻R1、R2(阻值已知)等器材按图所示连接成实验电路,研究串联电路中的电流、电压、电阻的特点。实验中测得各电压表、电流表的示数记录如下表:

(1)根据表中_________的示数关系(填写表中的电表符号),可得到的初步结论是:在串联电路中,电流强度处处相等。

(2)根据表中电压表V1、V2和V的示数关系可得到的初步结论是:_______________________________。

(3)根据表中R1、R2的阻值和电压表V、电流表A2示数比值的关系可归纳出的结论是:_________________________________________________________________________。

(4)分析实验次数1、2和3中电压表V1和电流表A1示数的比值及电阻R1的阻值关系,可得出的结论是:___________________________________________________________。

答案

(1)电流表A1、A2

(2)在串联电路中,串联电路两端的总电压等于各导体两端电压之和。

(3)串联电路的总电阻等于各串联导体电阻之和。

(4)导体两端的电压与通过导体的电流的比值越大,该导体的电阻值越大。

选择题
阅读理解

 Have you ever wondered why you sometimes take an almost immediate liking to a person you have just met? We often get the first impression of a people based on the color of a person’s skin or the manner in which he or she dressed. Meaning is conveyed not only by words or verbal languages but also by nonverbal communication systems, such as body behaviors.

Nonverbal communication is important because we use the actions of others to learn about their affective emotional states .Our emotions are reflected in our posture, face, and eyes—be it fear, joy, anger, or sadness—so we can express them without ever saying a word .For this reason, most of us rely heavily on what we learn through our eyes.

Nonverbal communication is significant in human interaction because it is usually responsible for the first impressions. More importantly, those first messages usually influence the perception(感知) of everything else that follows. Even how we select friends and sexual partners is grounded in first impressions with nonverbal communication.

Nonverbal communication is important because it is culture-related. It is based on different beliefs, religions, values and customs in different cultures. When, where, how, and to whom people display his or her specific nonverbal behaviors is greatly affected by culture and context. Culture determines what the appropriate nonverbal behavior is. For example, feelings of friendship exist everywhere but their expression varies. It may be appropriate in some countries for man to embrace each other and for women to hold hands; in other countries these displays of affection may be shocking. Each culture has its own specific interpretation on nonverbal communication. What is acceptable in one culture may be completely unacceptable in another. One culture may determine that snapping fingers to call a waiter is acceptable; another may consider this gesture rude.

小题1: What is the best title of the passage ?

A.Nonverbal communication and first impression

B.Nonverbal communication is culture-related

C.Nonverbal and verbal communication

D.The importance of nonverbal communication小题2: We can know a person’s feeling through our eyes because_________.

A.we can see a person’s feeling on his face

B.a person’s emotions can be reflected through eyes

C.a person’s feeling can be reflected through his body languages

D.we can see a person’s feeling through his posture小题3: Which of the following statements is not True ?

A.Meaning can be conveyed both by words and body language.

B.We can use nonverbal communication to learn about a person’s emotional states.

C.We often get the first impression by what a person says.

D.The first impression can affect what we will do in the following.小题4:What can we conclude from the last paragraph ?

A.we can use different ways to express friendship.

B.each culture has its own specific interpretation on nonverbal communication.

C.snapping fingers to call a waiter is acceptable.

D.learning a country’s culture is very important.