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【单选题】
在水平地面上运动的小车车厢底部有一质量为m 1 =1kg的木块，木块和车厢通过一根轻质弹簧相连接，并处于静止状态，弹簧被拉伸且弹力大小为5N。此时在车厢的顶部用一根细线悬挂一质量为m 2 的小球，现对小车施加一水平力，使小车由静止开始运动，发现细线与竖直方向的夹角θ由0逐渐增加到37 0 （sin37 0 =0.6，cos37 0 =0.8），则在这段时间内（）A.
木块与小车始终保持相对静止，弹簧对物体的作用力始终没有发生变化
B.
随着小车加速度的增加，木块所受摩擦力逐渐增大
C.
当木块摩擦力为0时，tanθ=0.75
D.
小车以7.5m/s 2 的加速度向左做匀加速直线运动时，物体受到的摩擦力为3.5N
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举一反三
【简答题】按照数据监测方法的不同，入侵监测系统可以分为（）监测模型和（）监测模型两类。
【多选题】Choose one word from the following fourteen words to fill in the sentence. Just choose the corresponding Roman Latter . 请从下列14个单词中选出最合适的词,填入横线中。(注意:只填单词前的字母,不要直接填单词)(
A.
a flicker of doubt ;
B.
conferred to;
C.
contradictions ;
D.
convert;
E.
disinterested;
F.
given the third degree;
G.
lag behind;
H.
literal ;
I.
make for;
J.
reputation; K. sliding down; L. stampeded ; M. stand by; N. stand to; ) 6. That night Ruth’s father went to the boy’s house, and the boy was____(7)____to account what had happened. His romantic relationship with Ruth ended and he gained a poor ____(8)____for being immoral.
【单选题】The boy went to school as usual the next day after the accident, _____ nothing had happened at all. A. in case B. so that C. even if D. as though
A.
in case
B.
so that
C.
even if
D.
as though
【多选题】In the following table, there are 14 words/phrases; choose the right one to fill in the sentences. Each word/phrase could be used only once. Write the corresponding Roman Letter in each sentence. 请从下面...
A.
a flicker of doubt ;
B.
conferred to;
C.
contradictions ;
D.
convert ;
E.
disinterested;
F.
given the third degree;
G.
lag behind;
H.
literal ;
I.
make for;
J.
reputation; K. sliding down; L. stampeded ; M. stand by; N. stand to ;
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