如图(甲)所示,边长为L=2.5m、质量m=0.50kg的正方形绝缘金属线框,平

题型:计算题

问题:

如图(甲)所示,边长为L=2.5m、质量m=0.50kg的正方形绝缘金属线框,平放在光滑的水平桌面上,磁感应强度B=0.80T的匀强磁场方向竖直向上,金属线框的一边ab与磁场的边界MN重合。在力F作用下金属线框由静止开始向左运动,在5.0s内从磁场中拉出。测得金属线框中的电流随时间变化的图象如图(乙)所示。已知金属线框的总电阻为R=4.0Ω。

(1)试判断金属线框从磁场中拉出的过程中,线框中的感应电流方向?

(2)t=2.0s时,金属线框的速度?

(3)已知在5.0s内力F做功1.92J,那么,金属框从磁场拉出过程线框中产生的焦耳热是多少?

考点:右手定则电磁感应现象中的切割类问题
题型:计算题

氯胺酮麻醉属于()

A.静脉麻醉

B.分离麻醉

C.基础麻醉

D.区域麻醉

E.阻滞麻醉

题型:计算题

要扭转那种重固定资产积累、轻流动资金积累的偏见,必须保持固定资产投资与流动资金投资的合理比例。据经验,流动资金投资占全部投资的30%较为适宜。按有关文件规定,在安排新建企业或扩建老企业时,应安排一定数量的流动资金投资,避免项目建成后,因缺少流动资金而不能形成生产能力。 这段话的主旨是( )。

A.要控制固定资产投资的膨胀,加大对流动资金的投资

B.必须保持固定资产投资和流动资金投资的合理比例

C.今后要安排一定数量的流动资金投资

D.要加大对流动资金的投资,首先要扭转轻视流动资金积累的偏见

题型:计算题

反诉:是指在已经提起的诉讼中,被告针对与原诉有联系的行为,提起独立诉讼请求的行为。根据以上定义,下列行为属于反诉的是()。

A.老师起诉学生借钱不还,学生起诉老师剽窃

B.原告起诉离婚,被告请求法院确认婚姻关系本来就是无效

C.原告起诉,要求被告按买卖合同交货,被告起诉供货商未能按时交货

D.原告起诉被告居住的房屋所有权是他的,被告请求法院让原告偿还欠款

题型:计算题

阅读理解

     Tom was one of the brightest boys in the year, with supportive parents. But when he was 15 he

suddenly stopped trying. He left school at 16 with only two scores for secondary school subjects.One

of the reasons that made it cool for him not to care was the power of his peer(同龄人) group.

      The lack of right male(男性的 )  role models  in  many of their lives-at home and particularly in the

school environment(环境) --means  that  their  peers  are  the  only

people they have to judge themselves against.

     They don't see men succeeding in society so it doesn't occur to  them that chey could make something of themselves. Without male teachers as a role model, the effect of peer actions and street culture (文化)

is all-powerful. Boys want to be part of a club. However, schools can provide the environment for change, and provide the right role models for them. Teachers need to be trained to stop thal but not in front of a

child's peers. You have to do it one to one, because that is when you see the real child.

      It's pointless sending a child home if he or she has done. wrong. They see it as a welcome day off to

watch television or play computer games. Instead, schools should have special unil where a child who has done wrong goes for the day and gets advice about his problems-somewhere he can work away from his peers and go home after the other children.

1. Why did Tom give up studying?    

A. He disliked his teachers.

B. His parents no longer supported him.

C. lt's cool for boys of his age not to care about studies.

D. There were too many subjects in his secondary school.

2. What seems to have a bad effect on students like Tom?

A. Peer groups.          

B. A special unit.

C. The student judges.    

D. The horne environment.

3. What should schools do to help the problem schoolboys?   

A. Wait for their change patiently.

B. Train leaders of their peer groups.

C. Stop the development of street culture.

D. Give them lessons in a separate area.

4. A teacher's work is most effective with a schoolboy when he _________. 

A. is with the boy alone

B. teaches the boy a lesson

C. sends the boy home as punishment

D. works together with another teacher

题型:计算题

下列有关直线式组织结构的说法中不正确的是()。

A、形成一种自下而上的金字塔结构

B、机构简单、权责分明

C、决策迅速、高效管理

D、有利于发挥员工参与知识产权管理的积极性

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