试题与答案

如图所示,一个质量为m的小球从竖立在地面上的轻弹簧正上方某处自由下落,接触弹簧后

题型:多选题

题目:

如图所示,一个质量为m的小球从竖立在地面上的轻弹簧正上方某处自由下落,接触弹簧后将弹簧压缩,在压缩全过程中,弹簧均为弹性形变,那么(   )

A.当小球的动能最大时,弹性势能为零

B.当小球的动能减为零时,重力势能最小

C.当小球的动能减为零时,球的加速度最大,但不一定大于重力加速度值

D.当小球的动能减为零时,球所受弹力最大,且一定大于2mg

答案:

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参考答案:A解析:红细胞酶缺陷使红细胞容易破坏,寿命缩短,所以红细胞酶缺陷属于红细胞破坏过多引起的贫血。

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     Making Our Team Work Best

      Learning in school, we often work in small groups.But why? Is it necessary to work with others?

What if you feel comfortable doing a job by yourself ? In reality, however, after leaving school, you will

find out that almost all work in many fields is done in teams.

1.____

     Actually, a team is a group of individual people brought together in order to complete a task which

cannot be efficiently finished by any member of the group alone.The group may be temporary or it

may stay together for a long period.

2.____

      A type of team that we are familiar with are sports teams, which are made up of a certain numbers

of players.They work together to win a match.In fact, different numbers have different skills in a team.A team can only work well when all their members cooperate.The atmosphere in a team affects

the performance of the team, so the social relations within the team are important.

3.____

      Teams require leaders, and people who create ideas, who develop ideas, and people whose role is

to comment and help improve plans.People who identify problems and suggest solutions are needed

in a team, too.Every team member works in their most efficient way to make the whole team work

best.

4.____

      Regulations and rules help teams work well.But be careful.Working in a team, we have to take

into account how each individual member can work best.Some may work best on task alone; others

work best in groups.How the group task is divided depends on the personalities and abilities of the

individual in the group.

5.___

      In a dynamic (充满活力的) team, people with quite different personalities work well together.

Actually, their differences are the strength of the team.To make the best of working with our classmates, or to make our team work best, it is important to recognize the strengths and weaknesses of each individual of the group.

     To know someone's personality type and ability is to know a great deal about that individual person,

or to understand that person.To understand means that we can build strong relationship between

members of a team, and make the best use of each others' talents.

A.Knowing about Team Members

B.Functions of Rules and Regulations

C.Team Members and Their Roles

D.How a Team Works

E.A Sports Team

F.The Definition (定义) of a Team

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