试题与答案

如图所示,AB是一质量为m的均匀细直杆,A端靠在光滑的竖直墙壁上,B端置于水平地

题型:选择题

题目:

如图所示,AB是一质量为m的均匀细直杆,A端靠在光滑的竖直墙壁上,B端置于水平地面上,杆身与竖直方向夹角为θ,杆与地面的摩擦系数为μ,保持平衡,则此时杆与地面的摩擦力为(  )

A.mgtgθ

B.mgsinθ

C.μmg

D.μmg

答案:

答案:A

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题型:阅读理解
根据对话内容,从对话后的选项中选出能填入空白出的最佳答案,并在答题卡上将该项涂黑。选项中有两项多余选项。(共5小题:每小题一分,满分5分)
注意:E涂AB,F涂AC,G涂AD
A:Now,Mr John.I’ve read your own docter’s report.So you haven’t been feeling well lately.小题1:
B:Yes.It’s my leg,docter.My left leg.I’m suffering from frequent strange pain in it.
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B:It’s like boiling water running down my leg.It’s been getting worse lately too.I’v been losing sleep.
A: 小题3:
B:Yes,that’s right.It’s been keeping me awake.
A:Have you been getting tired lately after you have a walk?
B:Why?Yes,Yes,I have,docter.
A:Hmm…小题4:
B:Do you think it’s serious?
A:Probably not.
B:But…Docter Cook,my local docter think it’s only that I have been working too hard lately.
A: 小题5:Don’t worry.We’ ll find out soon.
A.What can I do for you?
B.Could you tell me what the pain is like?
C.I think we’d better give a few tests here in hospital.
D.You mean the pain’ s been keeping you awake?
E.It’s nothing serious.
F.Is that right?
G.That could be the reason.
 
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