给你图甲中的器材,请测出额定电压为2.5V的小灯泡的额定功率. (1)连接电路时

题型:问答题

问题:

给你图甲中的器材,请测出额定电压为2.5V的小灯泡的额定功率.

(1)连接电路时开关应______(填“断开”或“闭合”).

(2)把图甲中的实物电路连接完整,并在虚线框乙中画出对应的电路图;

(3)闭合开关前,图甲中滑动变阻器的滑片P应位于______(选填“A”或“B”)端.

(4)闭合开关后,移动变阻器的滑片,使电压表示数为______V,此时电流表示数如图丙所示,其示数为______A,则该小灯泡的额定功率是______W,小灯泡的电阻是______Ω;

(5)在实验中若发现电流表没有示数,而电压表有示数,则电路可能现的故障是:______.

考点:测量电功率的实验
题型:问答题

农村是中国革命的摇篮,农村是摧毁封建土地制度的阵地,农村是经济体制改革的先锋。下列历史活动中,开辟了农村包围城市独特革命道路的是

A.工农武装斗争

B.土地改革

C.创建人民军队

D.井冈山革命根据地的创建

题型:问答题

Part 1


·Read thefollowingpassage, eight sentences have been removed from the article.
·Choose from the sentences A-H the one whichfits each gap.
·For each gap (1-8) mark one letter (A-H) on the Answer Sheet.
·Do not mark any letter twice.
The single, decisive factor that made it possible for mankind to settle in permanent communities was agriculture. (1) Once people could control the production of food and be assured of a reliable annual supple of it, their lives changed completely.
Fanning was a revolutionary discovery. (2) With more food available, more people could be fed. Populations therefore increased. The growing number of people available for more kinds of work led to the development of more complex social structures. (3)
Farming the world over has always relied upon a dependable water supply. For the earliest societies this meant rivers and streams or regular rainfall. (4) Later communities were able to develop by taking advantage of the rainy seasons.
All of the ancient civilizations probably developed in much the same way, in spite of regional and climatic differences. (5) Heavier pottery replaced animal-skin gourds as containers for food and liquids. Cloth could be woven from wool and flax. Permanent structures made of wood, brick, and stone could be erected.
The science of mathematics was an early outgrowth of agriculture. People studied the movements of the moon, the sun, and planets to calculate seasons. (6) With a calendar it was possible to calculate the arrival of each growing season. Measurement of land areas was necessary if property was to be a factor in farming and housekeeping. (7) All of the major ancient civilizations in Mesopotamia, Egypt, the Indus Valley, and China emerged in the 4th millennium BC. Historians still debate over which one emerged first. It may well have been the Middle East, in an area called the Fertile Crescent. This region stretches from the Nile River in Egypt northward along the coast of former Palestine, then eastward into Asia to include Mesopotamia. (8) This kind of larming depended on the reproduction of seed, normally from grain crops.
A. It not only made settlements possible and ultimately the building of cities but it also made available a reliable food supply.
B. Later came measures of value as commodity and money exchange became common.
C. In this area people settled along the riverbanks and practiced field agriculture.
D. After farming was developed in the Middle East in about 6500 BC, people living in tribes or family units did not have to be on the move continually searching for food or herding their animals.
E. As villages grew, the accumulation of more numerous and substantial goods became possible.
F. With a food surplus, a community could support a variety of workers who were not farmers.
G. The first great civilizations grow up along rivers.
H. In doing so they created the first calendars.

题型:问答题

水准仪观测读数时产生了视差,其原因是()。

A.仪器架设不稳

B.目镜对光不良

C.圆水准气泡未居中

D.物镜对光成像与十字丝平面不重合

题型:问答题

现代色谱在()等几个方面发展比较突出。

A.新的分析方法

B.新的色谱硬件

C.色谱的联用技术

D.色谱理论

题型:问答题

下列关于信息安全说法正确的有()。

A.从国家层面来看,信息安全包括广播电视视网络、电信网络、互联网等基础信息网络安全

B.涉及国计民生的重要信息系统的安全,以及信息内容安全等方面,是保障信

C.信息安全要靠国家的公务人员来保障

D.关系到国家的经济安全、政治安全

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