下端封闭上端开口的玻璃管竖直放置着，玻璃管中装有适量的水，在把玻璃管由竖直放置逐

发布时间：2017-06-23 06:41 │ 来源：www.tikuol.com

题型：选择题

问题：

下端封闭上端开口的玻璃管竖直放置着，玻璃管中装有适量的水，在把玻璃管由竖直放置逐渐变为倾斜放置的过程中（水未溢出），水对玻璃管底部的压强[ ]

A．逐渐变大

B．逐渐变小

C．不变

D．无法确定

考点：液体压强的特点

题型：选择题

完形填空。

     Let's look at a fly, and see where it flies. First, it flies out   1   the window.   2  , it stands on   3   dirty things in the street, and then it flies back to the house and walks over your   4 .
     When a fly walks on the dirty things in the street, its   5   have got some germs   6   them. When the fly walks on your food with its dirty feet, it   7   the germs on your food.
     What can you   8   this?
     First, we learn that we mustn't leave dirty things in the street or on the ground near   9  . Second, we learn that all food must be covered so that flies may not  10  it. Third, we learn that flies often carry germs and we must kill them as soon as we see them.

( )1. A. to
( )2. A. First
( )3. A. some
( )4. A. food
( )5. A. body
( )6. A. in
( )7. A. carries
( )8. A. study from
( )9. A. the factory
( )10. A. arrive

B. of
B. Second
B. any
B. drink
B. feet
B. to
B. has
B. study for
B. our door
B. get

C. for
C. Third
C. every
C. cups
C. eyes
C. on
C. leaves
C. learn for
C. our house
C. arrive in

D. in
D. Fourth
D. each
D. bowls
D. head
D. over
D. takes
D. learn from
D. a window
D. get to

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如图是建筑工地常用的一种“深坑打夯机”，电动机带动两个滚轮匀速转动将夯杆从深坑提上来，当夯杆底端刚到达坑口时，两个滚轮彼此分开，将夯杆释放，夯杆在重力作用下落回深坑。夯实坑底。已知两个滚轮边缘的线速度恒为v=4m/s，滚轮对夯杆的压力F_N=2×10⁴N，滚轮与夯杆间的动摩擦因数=0.3，夯杆质量m=1×10³kg，坑深h=6.4m，取g=10m/s²，求：

（1）夯杆自坑底开始匀加速上升，当速度增加到4m/s时，夯杆上升的高度；

（2）夯杆自坑底上升的最大高度；

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1978年中共十一届三中全会在北京召开，这次会议确立的思想路线是

A．建设中国特色法律体系

B．坚持以经济建设为中心

C．建设中国特色社会主义

D．解放思想，实事求是

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2006年10月，中共十六届六中全会审议并通过了《中 * * 关于构建社会主义________若干重大问题的决定》。[ ]

A．和谐社会

B．文明社会

C．文化社会

D．法治社会

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题型：选择题

迁延性腹泻(persistingdiarrhea)

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