问题 实验题

某学习小组通过实验来研究电器元件Z的伏安特性曲线。他们在实验中测得电器元件Z两端的电压与通过它的电流的数据如下表

U/V0.000.200.501.001.502.002.503.00
I/A0.0000.0500.1000.1500.1800.1950.2050.215
 

现备有下列器材:

A.内阻不计的6V电源;

B.量程为0~3A的内阻可忽略的电流表;

C.量程为0~0.6 A的内阻可忽略的电流表;

D.量程为0~3V的内阻很大的电压表;

E.阻值为0~10Ω,额定电流为3A的滑动变阻器;

F.电键和导线若干。

(1)这个学习小组在实验中电流表选(填器材前面的字母)

(2)请你从下面的实验电路图中选出最合理的一个

(3)利用表格中数据绘出的电器元件Z的伏安特性曲线,如图所示,分析曲线可知该电器元件Z的电阻随U变大而(填“变大”、“变小”或“不变”);

(4)若把用电器Z接入如图所示的电路中时,电流表的读数为0.150A,已知A、B两端电压恒为2V,则定值电阻R0 阻值为_______Ω。(结果保留两位有效数字)

答案

(1)C(2分);(2)D(3分);(3)变大:(2分)(4)6.7-6.9之间均可

题目分析::(1):由数据表可知,电路中的最大电流为0.215A,所以电流表应选择C;

(2):从数据表可知要求电流从零调,所以变阻器应采用分压式接法;由于电流表与电压表均为理想电表,所以电流表采用外接法和内接法均可,故选D

(3)根据欧姆定律可知,,可知元件电阻随U的变大而变大.

(4)从图中可看出当电流为0.150A时,电器Z两端的电压为1V,所以定值电阻

问答题 简答题

甲食品制造公司,在发展初期一直采用传统的手工方式管理企业的日常运作,但是随着甲公司业务范围和规模的不断发展,公司的高层管理人员意识到传统管理方式无法进行有效的管理,于是在公司范围内实行全面的变革,决定采用先进的IT技术重塑企业的管理模式。对甲公司领导而言,他们希望通过运用信息系统,使整个公司的运营发生“蜕变”,公司能够重塑核心竞争力,朝着规范化、科学化的管理方向发展。比如,在系统实施的过程中,公司的领导并没有让员工一边使用信息系统,一边用手工的方式工作,因为员工在不熟悉新系统的情况下,必然会产生抵制心理,而“并行”实施的方法会为他们提供各种各样的理由不使用新系统,从而导致系统很难进一步实施。而且,由于甲公司门店很多,如果使用手工和系统“并行”的方式,在对账和盘点时又将是一笔笔“糊涂账”,对实施效果是非常不利的。所以管理人员决定尽量减少系统实施中的不必要环节,实行革命性的、彻底的变化。当然,员工对于公司变化也是非常敏感的,特别是如果涉及到自己的工作岗位的话,员工会产生强烈的抵触情绪。考虑到许多员工为公司的发展作出了很大的贡献,公司力求尽量不让员工下岗。于是,甲公司在对大部分流程进行了改进之后,虽然运用信息系统撤消了一些部门,但同时也增加了一些原来没有的部门和一些重要的工作岗位。比如,为了使信息系统能够顺畅地运作起来,公司增加了营运总调度和调度助理两个重要的岗位,专门负责公司的销售、运输、库存、计划的通盘运作和对记录后的数据进行分析,准确的数据加上这些部门的有效分析,使公司的运营决策有了科学的依据。要求:(1)简述选择战略变革的时机的三种类型,并确定甲公司选择战略变革时机的所属类型;(2)简述渐进性变革与革命性变革的区别,并确定甲公司所实施的战略变革属于这两个变革中的哪一个变革?(3)简述战略变革的发展阶段以及各阶段的特点;(4)简述战略变革的模式,并简要分析甲公司实施的战略变革的模式;(5)简述战略变革面临的障碍;(6)简述克服变革阻力的策略。

阅读理解

Different Kinds of Birds

Avocets

There are 4 different species of Avocet found around the world-Pied Avocet , Red-necked Avocet, Andean Avocet, and American Avocet. This bird is found in North and South America, Europe, and even Australia. This long-legged bird has webbed feet and an upturned, thin bill.

Bald Eagles

The bald eagle is found in wetlands and near coastlines. They have very large and broad wings, with a broad tail. The head and tail are white in color, which is the major distinguishable factor of the bald eagle. The long, hooked bill is yellow in color. They feed on fish, ducks, rabbits, geese, etc.

Eastern Bluebirds

These are around 61/2 inches in length .Such birds are found mainly in gardens woodlands, and orchards with the arrival of spring. Male Eastern Bluebirds are bright blue on the upper half and have a white belly. Female Eastern Bluebirds have a grayish head with shades of blue as well. New York and Missouri have named this creature as their state bird.

Flamingos

These pink-bodied birds with a unique beak, are generally found in large groups. The beaks are capable of removing mud before they can eat their food. Flamingos can be found in many African countries, areas of Florida, and one particular type of species is found only in the Andean highlands.

Kingfishers

There are over 90 various species of Kingfishers found in the woodland areas as well as wetlands across the world. They are excellent divers when it comes to catching fish in the rivers. Their pointed bills are what help them bag the catch. Kingfishers have good eyesight whether they are in air or underwater.

小题1:____ most probably mean the same.

A.Bill and beak

B.Head and beak

C.Bill and belly

D.Leg and feet小题2:Which of the following is true?

A.Eastern Bluebirds are all blue in color.

B.Avocets can be found around the world.

C.The white head and tail make Bald Eagles distinguishable.

D.More Kingfishers can be found in wetlands than in the woodland areas.小题3:Birds that can be found only in the Andean highlands are ________.

A.Bald Eagles

B.Female Eastern Bluebirds

C.Andean Avocets

D.one special type of Flamingos小题4:It can be inferred from the passage that what Bald Eagles and Kingfishers have in common is their____.

A.habitats

B.shapes

C.ability to catch fish

D.eyesight in air or under water