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问题 计算题

(11分)如图10所示，长为L、间距为d的平行金属板间，有垂直于纸面向里的匀强磁场，磁感应强度为B，两板不带电，现有质量为m、电荷量为q的带正电粒子(重力不计)，从左侧两极板的中心处以不同速率v水平射入，欲使粒子不打在板上，求粒子速率v应满足什么条件？、

答案

v<或v>

设粒子刚好打在上极板左边缘时(如图所示)．

R1＝，

又R1＝，解得v1＝.

设粒子刚好打在上极板右边缘时，

由图知：R22＝L2＋(R2－)2，所以R2＝，

又R2＝，解得v2＝.

综上分析，要使粒子不打在极板上，其入射速率应满足以下条件：v<或

v>.

单项选择题 A1/A2型题

以下不属于卡马西平不良反应的是（）。

A.过敏性皮疹

B.引起窦性心动过缓

C.体位性低血压

D.肝功能异常

E.不自主运动
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单项选择题

Anthropology is the study of human beings as creatures of society. It (1) its attention upon those. physical characteristics and industrial techniques, those conventions and values, which (2) one community from all others that belong to a different tradition.

The distinguishing mark of anthropology among the social sciences is that it includes for serious study other societies (3) our own. For its purposes any social (4) of mating and reproduction is as significant as our own. To the anthropologist our customs and those of a New Guinea tribe are two possible social schemes for (5) a common problem, and in so far as he remains an anthropologist he is (6) to avoid any weighting of one (7) the other. He is interested in human behavior, not as it is shaped by one tradition, our own, but as it has been shaped by any tradition (8) He is interested in a wide (9) of custom that is found in various cultures, and his object is to understand the way in which these cultures change and (10) , the different forms through which they express themselves and the (11) in which the customs of any peoples function in the lives of the (12) .

Now custom has not been commonly regarded as a (13) of any great moment. The inner workings of our own brains we feel to be uniquely (14) of investigation, but custom, we have a way of thinking, is behavior at its most commonplace. (15) , it is the other way round. Traditional custom is a mass of detailed behavior more astonishing than (16) any one person can ever evolve in individual actions. Yet that is a rather (17) aspect of the matter. The fact (18) first rate importance is the predominant role that custom (19) in experience and belief, and the very great varieties it may (20)

6（）

A.acknowledged

B.authorized

C.bound

D.credited
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