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          題目列表(包括答案和解析)

          I、在探究滑動(dòng)摩擦力與什么因素有關(guān)的實(shí)驗(yàn)中,
          (1)木塊在水平放置的毛巾、木板、棉布的表面上運(yùn)動(dòng)時(shí)必須保持
          勻速直線
          勻速直線
          運(yùn)動(dòng),根據(jù)
          平衡力
          平衡力
          的原理,得到摩擦力的大。
          (2)分析以下實(shí)驗(yàn)數(shù)據(jù),得出的結(jié)論是:
          小車受到的摩擦力越小,小車滑行的距離越長(zhǎng),速度減小的越慢
          小車受到的摩擦力越小,小車滑行的距離越長(zhǎng),速度減小的越慢

          實(shí)驗(yàn)次數(shù) 接觸面的材料 壓力(N) 滑動(dòng)摩擦力(N)
          1 木塊與木板 4 0.8
          2 木塊與木板 6 1.2
          3 木塊與棉布 6 2
          4 木塊與毛巾 6 2.5
          II、某學(xué)生在探究“彈簧的長(zhǎng)度與外力的變化關(guān)系”時(shí),利用圖所示器材和數(shù)只鉤碼做實(shí)驗(yàn),并記錄了相應(yīng)的數(shù)據(jù),如表
          鉤碼重(N) 0 0.5 1.0 1.5 2.0 2.5 3.0
          指針位置(cm) 2 3 4 5 6 7 7.5
          (1)這項(xiàng)研究在實(shí)際中的應(yīng)用是
          彈簧測(cè)力計(jì)
          彈簧測(cè)力計(jì)
          ;
          (2)分析數(shù)據(jù),你可得出的結(jié)論是
          在彈性限度內(nèi),彈簧的伸長(zhǎng)跟受到的拉力成正比
          在彈性限度內(nèi),彈簧的伸長(zhǎng)跟受到的拉力成正比
          ;
          (3)該同學(xué)作了彈簧受力與彈簧伸長(zhǎng)長(zhǎng)度的關(guān)系圖,如圖.其中正確的圖象是
          b
          b
          ;
          (4)由圖可知,該彈簧受到的拉力每增加1牛頓,彈簧的伸長(zhǎng)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(顫抖).  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(講究實(shí)際的) 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.
          【小題1】
          A.startingB.destroyingC.showingD.doing
          【小題2】
          A.rainB.fogC.snowD.cloud
          【小題3】
          A.suitB.jacketC.capD.coat
          【小題4】
          A.thinkB.guessC.seeD.check
          【小題5】
          A.easyB.shortC.safeD.long
          【小題6】
          A.heardB.believedC.noticedD.expected
          【小題7】
          A.bravelyB.nearlyC.onlyD.usually
          【小題8】
          A.suddenlyB.immediatelyC.madlyD.calmly
          【小題9】
          A.wouldB.couldC.shouldD.might
          【小題10】
          A.blouseB.sweaterC.dressD.raincoat
          【小題11】
          A.ran awayB.woke upC.fell illD.got hurt
          【小題12】
          A.saleB.sizeC.colorD.offer
          【小題13】
          A.thoughB.untilC.sinceD.if
          【小題14】
          A.warmB.coldC.sunnyD.dark
          【小題15】
          A.knewB.matteredC.lovedD.blamed
          【小題16】
          A.deeplyB.wronglyC.finallyD.firmly
          【小題17】
          A.envyingB.watchingC.holdingD.wearing
          【小題18】
          A.keepB.buyC.borrowD.throw
          【小題19】
          A.environmentB.placeC.windD.situation
          【小題20】
          A.denyB.a(chǎn)greeC.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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