受拉杆件横截面积为40mm2,许用应力为250MPa,所能承受的最大载荷是23()。

题型:单项选择题

问题:

受拉杆件横截面积为40mm2,许用应力为250MPa,所能承受的最大载荷是23()。

A.10kN

B.6.25kN

C.0.16kN

D.100kN

考点:钻井柴油机工钻井柴油机工(高级)钻井柴油机工(高级)题库
题型:单项选择题

请根据短文内容及首字母提示填空,使短文意思完整、通顺。

     Once there was a very little beautiful, smart girl in my class. I believed she was perfect. When it came

to the time for my birthday, I i __1___ her to my birthday, and she came. We had a very good time and

e __2___ was very happy. I thought we had become good friends. A few months l__3__    it was her

birthday. I bought a special necklace for her. I could not help thinking about how happy she must be

opening my g__4__  . It made me very excited to imagine the surprise on her face.

     I asked her w___5__ her birthday party was going to be. She replied in a cold v__6___ , "Why do

you want to know? You are not invited; you are just a dork with glasses!"

     Her words h__7___  me. I just wanted to be her friends. I felt really b__8___ when she said that and

I just stood there to look at her. Everyone s__9___ by her came to stand next to me. Then we all left.

     That day I came to understand that t__10__ someone looks perfect, he or she may not be.

题型:单项选择题
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

题型:单项选择题

下列与色素性荨麻疹关系密切的是()

A.嗜碱性粒细胞

B.肥大细胞

C.食物过敏

D.寒冷性刺激

E.淋巴细胞

题型:单项选择题

分半信度通常是在测验实施后将测验按奇、偶数分为等值的两半,并分别计算每位被试在两半测验上的得分,求出这两半分数的相关系数。这个相关系数就代表了()取样的一致性程度。

A.原测验

B.所有条目之间

C.题目与分测验之间

D.两半测验

题型:单项选择题

胃液采集术的禁忌证是

A.便潜血阳性患者

B.疑为十二指肠溃疡者

C.有明确食管静脉曲张者

D.疑为胃溃疡者

E.疑为胃癌者

更多题库