某同学在做“研究匀变速直线运动”实验时,从打下的若干纸带中选出了如下图所示的一条

题型:问答题

问题:

某同学在做“研究匀变速直线运动”实验时,从打下的若干纸带中选出了如下图所示的一条纸带,已知打点计时器使用电源频率为50Hz,每两个相邻计数点间有四个点没有画出,则纸带上相邻两个计数点间的时间间隔为______s.如果用S1、S2、S3、S4、S5、S6来表示从O点开始各相邻两个计数点间的距离,用T表示两相邻记数点的时间间隔,则该匀变速直线运动的加速度的表达式为a=______(用符号写出表达式,不要求计算).打F点时物体的速度大小为vF=______m/s.(答案均要求保留3位有效数字)

考点:实验:探究小车速度随时间变化的规律
题型:问答题

根据情景和所给的首字母,在空格内填入一个适当的单词,使对话意思完整。

     Look! This is a p  1   of my family. The girl is my c   2  , Kate. She works hard and a    3    goes to school

early b  4   her schoo1 isn't near her home. She needs h   5   an hour to get there. She has four classes in the

morning. She has an A  6   lesson once a w   7    . She has English classes f   8   Monday to Friday. She likes l   9   English very much. She says it's her f  10    subject.

题型:问答题

阅读理解。

     Have you ever complained (抱怨) why life is so tiring? Does the sky sometimes seem dark to you?

Are your studies sometimes not successful? Well, friends, cheer up and smile all the time. If you see

the world with your warm heart, you'll find that the whole world smiles to you.

     While in school, sometimes you are tired of your lessons, but have you ever noticed the happy smile

on your teacher's face when you did a good job?

     One day it is fine. Just before you want to go out, it suddenly starts to rain. Maybe you would feel

very sad and start complaining about the weather. But dear friends, why don't you sit down and listen to

the free concert that the nature offers you? And with the timely (及时的) rain, crops in the fields will

grow better and better and farmers will have a better harvest.

     Although everyone wants to succeed in what he tries to do, sometimes failure (失败) can't be avoided.

I think failure is not terrible, and the terrible thing is that we are afraid of it and give up hope. When we face

failure, we must be confident (信心) of ourselves, draw a useful lesson from it and try our best to finish

what we have decided to do. As a popular saying goes, "Failure is the mother of success."

    Attitude (态度) decides everything. With an optimistic (乐观) attitude life is easy and pleasant. Let's

smile to whatever we meet and the whole world will smile to us.

1. People sometimes complain _____.

A. the sky is always dark

B. their studies are successful

C. they see the world with their heart

D. life is tiring

2. According to (根据) the passage, in school, _____.

A. the students don't like their lessons

B. the teachers will be happy if the students do good jobs

C. the teachers don't like their teaching

D. the teachers are tired of their work

3. If there is a timely rain, _____.

A. you want to go out

B. you can listen to a concert

C. crops in the fields will grow better

D. farmers can't have a good harvest

4. When we face failure, we _____.

A. must be confident of ourselves

B. shouldn't be afraid of it

C. shouldn't give up hope

D. all of the above

5. The best title (题目) of this passage is _____.

A. Smile and the World Smiles to You

B. Complaining About Life

C. Failure is the Mother of Success

D. It is Very Hard to Succeed

题型:问答题

男,72岁,因呼吸困难,双下肢水肿、尿少2天入院。既往有慢性咳嗽、咳痰史25年,冬季加重。以下检查中对诊断肺心病最有帮助的为()。

A.心电图检查示ST-T改变

B.胸部正位X线检查示心尖上翘或圆尖

C.肺功能检查示弥散功能障碍

D.X线检查示肺纹理粗乱,双下肺斑片影

E.心电图检查示Rvl+Sv5≤1.02mV

题型:问答题

与急性血吸虫病鉴别的疾病主要包括()

A.细菌性痢疾

B.阿米巴肝脓肿

C.伤寒

D.粟粒性肺结核

E.病毒性肝炎

题型:问答题

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