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问题 选择题

一根弹簧的下端挂一重物，上端用手牵引使重物向上做匀速直线运动．从手突然停止到物体上升到最高点时止．在此过程中，重物的加速度的数值将（　　）

A．逐渐增大

B．逐渐减小

C．先减小后增大

D．先增大再减小

答案

物体匀速运动过程，弹簧对物体的弹力与重力二力平衡；

手突然停止运动后，物体由于惯性继续上升，弹簧伸长量变小，弹力减小，故重力与弹力的合力变大，根据牛顿第二定律，物体的加速度变大；

故选A．

填空题

When I tell people that I’m a professor of communication, they often are confused (1) what the term "communication" means. Many people think mass communication is the (2) type of communication, but mass communication is only one form of communication. The study of mass communication focuses on messages that are (3) over (4) such as television, newspapers, and radio. Other areas of (5) focus on the messages individuals send to one another. Some of the major contexts in which communication is studied (6) the interpersonal context, the organizational context, and the intercultural context. A scholar studying (7) communication, for example, might examine how married couples (8) with misunderstandings and the effects these misunderstandings have on (9) satisfaction. Organizational communication scholars, on the other hand, might study (10) the communication styles used by managers and their subordinates influence productivity and efficiency in a company or factory.
My area of specialization is intercultural communication. Intercultural communication is an (11) field of study which incorporates research from disciplines (12) as social psychology, sociology, cultural anthropology, sociolinguistics, and of course, communication. One of the (13) important areas of research addressed by intercultural scholars is how misunderstandings can be (14) when people communicate with Others from different (15) . To understand the process of intercultural communication, we must study how individuals’ cultural backgrounds (16) their communication behaviors.
The area of intercultural communication is a relatively new (17) of study even in the United States. While most Chinese students studying communication in the United States (18) on mass communication, there are some who are interested in intercultural communication and plan to return to China to teach and (19) research in this area. The work of these Chinese scholars on intercultural communication is important because it will help improve (20) between Chinese and Americans in the future.
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问答题 简答题

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