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题目列表(包括答案和解析)

I、在探究滑动摩擦力与什么因素有关的实验中,
(1)木块在水平放置的毛巾、木板、棉布的表面上运动时必须保持
匀速直线
匀速直线
运动,根据
平衡力
平衡力
的原理,得到摩擦力的大小.
(2)分析以下实验数据,得出的结论是:
小车受到的摩擦力越小,小车滑行的距离越长,速度减小的越慢
小车受到的摩擦力越小,小车滑行的距离越长,速度减小的越慢

实验次数 接触面的材料 压力(N) 滑动摩擦力(N)
1 木块与木板 4 0.8
2 木块与木板 6 1.2
3 木块与棉布 6 2
4 木块与毛巾 6 2.5
II、某学生在探究“弹簧的长度与外力的变化关系”时,利用图所示器材和数只钩码做实验,并记录了相应的数据,如表
钩码重(N) 0 0.5 1.0 1.5 2.0 2.5 3.0
指针位置(cm) 2 3 4 5 6 7 7.5
(1)这项研究在实际中的应用是
弹簧测力计
弹簧测力计

(2)分析数据,你可得出的结论是
在弹性限度内,弹簧的伸长跟受到的拉力成正比
在弹性限度内,弹簧的伸长跟受到的拉力成正比

(3)该同学作了弹簧受力与弹簧伸长长度的关系图,如图.其中正确的图象是
b
b

(4)由图可知,该弹簧受到的拉力每增加1牛顿,弹簧的伸长增加
2
2
厘米.

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—I’m leaving for Canada on a study trip next week.
—___________________.
A.Enjoy your timeB.That’s all right
C.You’re welcomeD.It’s a pleasure

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—I think honesty is the most important thing in doing everything.
—__________________.
A.All rightB.Never mindC.I think so, tooD.Yes, please

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I will never forget the two impressive things that happened last winter. One of my classmates and I were   36  our project work late at night on my university's campus far from home.  Since there was   37  in the forecast, I had worn a winter   38  to school that day with a raincoat in my bag.
Throughout our work on the project, I could   39  that my friend was tired from a very long day working.  As we stepped outside to begin the   40  walk home, I   41  she was shivering(颤抖).  The temperature had dropped to the low thirties (Fahrenheit) and she   42  had a sweater on. I   43  offered her my warm jacket. She accepted it and asked me what I   44  wear then.  I told her I had another one and pretended that my   45  was a jacket.  She said later that she   46  the next morning and the first thing on her mind was feeling moved about my   47  of the jacket.
Coincidentally(碰巧), the next day I went to an open-air play and I was freezing   48  I didn’t expect it to be so   49 .  A person who I hardly   50  insisted that I wear his jacket.  I was   51  touched by this warm gesture.  He was so matter-of-fact(讲究实际的) about me   52  his coat, too:  he simply took it off and handed it to me telling me that I should   53  it. I used to think that this vast universe was a cold   54 .  It turns out that even when the temperature drops low, the people never   55  to warm each other's hearts.
【小题1】
A.startingB.destroyingC.showingD.doing
【小题2】
A.rainB.fogC.snowD.cloud
【小题3】
A.suitB.jacketC.capD.coat
【小题4】
A.thinkB.guessC.seeD.check
【小题5】
A.easyB.shortC.safeD.long
【小题6】
A.heardB.believedC.noticedD.expected
【小题7】
A.bravelyB.nearlyC.onlyD.usually
【小题8】
A.suddenlyB.immediatelyC.madlyD.calmly
【小题9】
A.wouldB.couldC.shouldD.might
【小题10】
A.blouseB.sweaterC.dressD.raincoat
【小题11】
A.ran awayB.woke upC.fell illD.got hurt
【小题12】
A.saleB.sizeC.colorD.offer
【小题13】
A.thoughB.untilC.sinceD.if
【小题14】
A.warmB.coldC.sunnyD.dark
【小题15】
A.knewB.matteredC.lovedD.blamed
【小题16】
A.deeplyB.wronglyC.finallyD.firmly
【小题17】
A.envyingB.watchingC.holdingD.wearing
【小题18】
A.keepB.buyC.borrowD.throw
【小题19】
A.environmentB.placeC.windD.situation
【小题20】
A.denyB.agreeC.helpD.stop

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I would appreciate it _______ you call back this afternoon for the doctor’s appointment.?
A.untilB.if?
C.whenD.that?

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