如图所示装置中,杠杆和滑轮的重力及滑轮的摩擦均可忽略不计,杠杆AB 可以绕O点在

题型:选择题

问题:

如图所示装置中,杠杆和滑轮的重力及滑轮的摩擦均可忽略不计,杠杆AB 可以绕O点在竖直平面内自由转动,A端通过竖直方向的轻绳与滑轮组相连,在B端用一轻绳沿竖直方向将杠杆拉住,使其始终保持水平平衡,在滑轮组的下方,悬挂一圆柱形的物体,此物体被浸在圆柱形容器内的液体中。已知杠杆O点两侧的长度关系为AO=2OB,圆柱形物体的底面积为10cm2、高为12cm,圆柱形容器的底面积为50cm2。若容器中的液体为水,在水深为20cm 时物体的上表面恰与水面相平,此时杠杆B端绳上的拉力为F1;打开圆柱形容器下方的阀门K,将水向外释放,直到物体露出水面的体积为其总体积的2/3时,将阀门K关闭,此时杠杆B端绳上的拉力为F2,且F1:F2=3:4。若容器中液体为某种未知液体,其质量与最初容器中的水的质量相等,此时未知液体的深度为18cm,杠杆B端绳上的拉力为F3。取g=10N/kg,则

[ ]

A.圆柱形物体的密度为2g/cm3

B.作用在B端的拉力F3大小为1.52N

C.未知液体的密度为1.2g/cm3

D.未知液体对圆柱形容器底部的压强为1980Pa

考点:液体压强的计算
题型:选择题

2008年是农村改革开放三十周年。30年来,我们党对农村改革发展的认识不断得到深化。党的十六大就提出了统筹城乡经济社会发展。一个多月之后,中央召开农村工作会议,要求粑解决“三农”问题作为全党工作的重中之重。十六届五中全会上,中央提出了建设社会主义新农村的重大历史任务。十六届六中全会将逐步扭转城乡发展差距扩大的趋势、建立覆盖城乡居民的社会保障体系、逐步实现基本公共服务均等作为重要内容。党的十七大就如何统筹城乡发展、建设新农村提出了新的要求,一是走中国特色的农业现代化道路,二是形成城乡经济发展一体化的经济格局,三是要建立以工促农、以城带乡的长效机制。

上述材料体现了认识论的哪些道理?

________________________________________________________________________________________________________________________________________________________________

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妇女一生中总共有多少个卵泡发育成熟()

A.1000个

B.1500个

C.100个

D.400个

E.50个

题型:选择题

(B)

Sixty-year-old grandmother, Fiona McFee, is going to stop working next year and she decided to realize a childhood dream and sail around the coast of Scotland in a small boat. Although the inside of the boat is very cosy it has no running water or electricity. Fiona says she can live without these things but she plans to take her small CD player, her hot water bottle and a bag of books to make sure life isn’t too uncomfortable.

We asked her if she was afraid of being at sea for so long. She said, “Well, I’m going to take a good compass (指南针). Anyway I’m not afraid of death because I love the sea---I just hope it loves me.” Fiona certainly has plenty of energy; in her spare time, she enjoys playing the piano, rock-climbing, canoeing and dancing. Although she is sixty, she doesn’t want to have a quiet and peaceful life. “I’m looking forward to having fun in the rest of my life and that’s exactly why I’d like to be a sailor for a while.”

小题1:The underlined word cosy in the first paragraph means ____ .

A.bright

B.dirty

C.comfortable

D.dark小题2:When Fiona McFee said “---I just hope it loves me.” What she meant was ____

A.Of course , it loves me , since I love it .

B.If I love it , it should love me.

C.I hope it will bring me a safe sailing as a return for my love of it .

D.I hope it will save my life when I am in time of danger .小题3: The reason why she would like to have the sail is that ____.

A.she thinks it will be very exciting

B.she likes sports and enjoys canoeing

C.she has decided to realize a childhood dream

D.she wants to be still active when she gets old小题4:What kind of person would you say the old woman is ?

A.Someone who does not show what she is feeling .

B.Someone who is very proud and sure of her success .

C.Someone who doesn’t use her head much .

D.Someone who is open , honest and brave .小题5:The best title for this passage is ____ .

A.Life Begins at Sixty

B.A Round Coast Sail

C.An Old Woman Sailor

D.An Unusual Hobby(爱好)

题型:选择题

绝大数血浆蛋白质来自于

A.肝合成
B.肾合成
C.肺合成
D.浆细胞合成
E.消化道吸收

题型:选择题

以下哪一项不属于需同变电站监控信息变更申请单一同上报的技术资料()

A、一次接线图

B、保护配置清单

C、信息表(调控信息表和信息对应表)

D、设备调度命名文件

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