马航MH370的失联事件深深的牵动着国人的心。我国“蛟龙”号潜水_爱下问搜题

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问题填空题

马航MH370的失联事件深深的牵动着国人的心。我国“蛟龙”号潜水器做好了随时参与水下搜救的准备，该潜水器下潜的最大深度达到了7062m。当该潜水器从3km深处下潜到5km深处时，其上下表面受到海水压力差的大小变化情况是（填“变大”“变小”或“不变”）。当下潜到7km深处时，它承受的海水压强是 Pa（取ρ海水=1×10³kg/m³）。

答案

不变；6.86×10⁷（或7×10⁷）

题目分析：液体压强随着深度的增加而增大，潜水器从3km深处下潜到5km深处时，所受压强增大，但排开水的体积不变，由阿基米德原理知所受浮力大小不变，其上下表面受到海水压力差即浮力的大小变化情况是不变；当下潜到7km深处时，它承受的海水压强是P=ρ_海水gh=1×10³kg/m³×10N/kg×7000m=7×10⁷pa（g取9.8N/kg时为6.86×10⁷pa）。

完形填空

In 2004,I was 22 years old and had just come back to Brazil after 14 months in England,holding my Cambridge Proficiency certificate.After nervously 21 a short training course,I began to give classes to my 12 students,all of them older than I was. I 22 hard to remain clam in class and 23 they wouldn't find out how unconfident I felt most of the time.I was quite _24_,actually,until the end of 25 and the night of the final oral test.
The test was going to start at 7 pm,and at 6:50, I_ 26 myself in the teachers bathroom to 27 all the test questions again.I really wanted to learn the 28 by heart so no one would think I was an inexperienced tester.The 29 is,I actually locked myself in the bathroom.I 30 couldn't get out!The bell rang at 7 pm and I could hear the noise in the halls 31 the students went to their rooms.I tried hard to 32 the bathroom door,but failed.
I heard the cleaning lady’s voice and asked for help as 33 as I could, However, she wasn't exactly a thoughtful person, and started 34 ：“Diana’s locked in the bathroom!”Shame had fallen upon me! 35 , the course director, the secretary and some teachers were outside the bathroom trying to get me out, and, 36 ,my students gathered outside too, happily saying things like“Aren’t we 37 ! No test today!”All I could do was 38 , and my entire 39 was waiting for me outside, naughty smiles on their faces.“ 40 ！Teacher.”They said,“We know you are human too!”
They all passed their test.True to the Brazilian style, we all went out for a beer afterwards, and laughed the whole thing off.

D．put forward

B．instructions

B．Soon enough

A．to my amazement

B．to my delight

C．to my surprise

D．to my horror

B．comfortable

B．Congratulations

C．Don’t be angry

D．Don’t worry

单项选择题

对表结构的修改是在下面______对话框中完成的。

A．表设计器

B．数据库设计器

C．表达式生成器

D．浏览窗口