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

发布时间：2017-07-29 18:40 │ 来源：www.tikuol.com

题型：选择题

问题：

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

考点：摩擦力的大小摩擦力的种类杠杆的平衡条件

题型：选择题

完形填空。

    Mr. Zhou and his students are on the train. Everyone is   1 . They'll arrive in Shanghai. Now, they
are   2   their way to their sister school by   3 . The school is not far   4   their hotel. Mr. Zhou becomes
more excited. He is from Shanghai. His parents and his friends will be glad   5   him. He and his students
are talking   6   their plan in the bus. First, they will study in their sister school   7  months and then they
will see some   8   places in Shanghai. About four months   9 , they'll go  10  Nanjing.

( )1. A. excites
(    )2. A. in
(   )3. A. train
(   )4. A. from
(   )5. A. to see
(    )6 A. about
(    )7. A. in
(    )8. A. interest
(    )9. A. after
(    )10. A. back

B. excited
B. for
B. plane
B. to
B. see
B. for
B. for
B. interested
B. later
B. back to

C. exciting
C. on
C. bike
C. with
C. seeing
C. on
C. at
C. interesting
C. On
C. to back

D. excite
D. to
D. bus
D. for
D. to look
D. with
D. after
D. interests
D. for
D. back in

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题型：选择题

在( )里填上适当的数。

1米=( )分米=( )厘米

40厘米+6分米=( )米

58米19米=( )米

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发行价格区间向中国证监会发行部报备后，发行人及其保荐机构应刊登（）。

A.定价公告

B.初步询价公告

C.初步询价结果公告

D.网下配售结果公告

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Your early establishment of L/C will enable us to ship your order ______ very good time.

A．in
B．at
C．on
D．within

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题型：选择题

调制解调器的主要作用是用【】通信信道传输数字信号。

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