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已知地面附近高度每升高12m，大气压降低1mmHg．为了利用大气压这一微小变化测量不同地点的高度差，某实验小组设计了如图所示的实验装置，在一个密闭的玻璃瓶的塞子上插入一根两端开口且足够长的细玻璃管，瓶内有一定量的水和空气．由于内外压强差，细玻璃管内水面与瓶内水面有一定的高度差h．现将此装置放在温度为27℃、大气压为750mmHg的A处，测得h=204mm．（不计水面升降引起的瓶内空气体积的变化，水银的密度为13.6×103kg/m3）

（1）将装置缓慢地从A处平移另一高度的B处，待稳定后发现水柱升高了40.8mm，若AB两地的温度相同，则B处______（选填：“高于”或“低于”）A处，AB间高度差为______m；

（2）再先将此装置平移另一高度的C处，稳定后发现水柱同样升高了40.8mm，但C处比A处的温度高1℃，则AC间高度差为______m．

答案

（1）将装置缓慢地从A处平移另一高度的B处，待稳定后发现水柱升高了40.8mm，设大气压降低了hmmHg，毛细管中水面上升hmm×13.6=40.8mm，

解得h=

40.8
13.6
=3mmHg，故AB间高度差为△h=3×12m=36m；

（2）大气压为750mmHg，在A处时，瓶内气体压强为：P1=750mmHg+

204
13.6
mmHg=765mmHg；

根据理想气体状态方程，有

P1V1
T1
=
P1V2
T2
，

代入数据解得：P2=767.55mmHg；

故B处大气压强PPB=P2-Ph=767.55mmHg-

(204+40.8)mmHg
13.6
=749.55mmHg；

故A、B间的高度差为：△h=（750-749.55）×12=5.4m；

故答案为：（1）高于，36；（2）5.4

单项选择题 A1/A2型题

编制爱德华个性偏好量表的理论基础是（）。

A.马斯洛的需要层次理论

B.莫瑞的人类需要理论

C.奥雷姆的需要理论

D.霍兰德的职业兴趣理论

E.罗尔的职业兴趣理论
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问答题

The first mention of slavery in the statutes of the English colonies of North America does not occur until after 1660--some forty years after the importation of the first Black people. Lest we think that slavery existed in fact before it did in law, Oscar and Mary Simon assure us that the status of Black people down to the 1660’s was that of servants. (46) A critique of the Simons’ interpretation of why legal slavery did not appear until the 1660’s suggests that assumptions about the relation between slavery and racial prejudice should be reexamined, and that explanations for the different treatment of Black slaves in North and South America should be expanded.
(47) The Simons explain the appearance of legal slavery by contending that, during the 1660’s, the position of White servants was improving relative to that of Black servants. Thus, the Simons argue, Black and White servants, heretofore treated alike, each attained a different status. There are, however, important objections to this argument. First, the Simons cannot adequately demonstrate that the White servant’s position was improving during and after the 1660’s; several acts of the Maryland and Virginia legislatures indicate otherwise. Another flaw in the Simons’ interpretation is their assumption that prior to the establishment of legal slavery there was no discrimination against Black people. It is true that before the 1660’s Black people were rarely called slaves. But this should not overshadow evidence from the 1630’s on that points to racial discrimination without using the term slavery. Such discrimination sometimes stopped short of lifetime servitude or inherited status--the two attributes of true slavery--yet in other cases it included both. (48) The Simons’ argument excludes the real possibility that Black people in the English colonies were never treated as the equals of White people.
This possibility has important ramifications. (49) If from the outset Black people were discriminated against, then legal slavery should be viewed as a reflection and an extension of racial prejudice rather than, as many historians including the Simons have argued, the cause of prejudice. In addition, the existence of discrimination before the advent of legal slavery offers a further explanation for the harsher treatment of Black slaves in North than in South America. (50) Frey and Terry have rightly argued that the lack of certain traditions in North America--such as a Roman conception of slavery and a Roman Catholic emphasis on equality--explains why the treatment of Black slaves was more severe there than in the Spanish and Portuguese colonies of South America. But this cannot be the whole explanation since it is merely negative, based only on a lack of something.
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