电子所带电荷量最早是由美国科学家密立根通过油滴实验测出的.油滴实验的原理如图所示

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问题:

电子所带电荷量最早是由美国科学家密立根通过油滴实验测出的.油滴实验的原理如图所示,两块水平放置的平行金属板与电源连接,上、下板分别带正、负电荷.油滴从喷雾器喷出后,由于摩擦而带电,油滴进入上板中央小孔后落到匀强电场中,通过显微镜可以观察到油滴的运动情况.忽略空气对油滴的浮力和阻力.若两块水平放置的平行金属板板间场强大小为8.0×103N/C,两板相距0.05m,则两板电势差为______V.板间有一带电量为2.0×10-11C的液滴恰好处于静止状态,则此液滴的质量为______kg.(g取10m/s2)

考点:滑动摩擦力、动摩擦因数力的合成共点力的平衡电场强度的定义式
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A nurse took a tired soldier to an old man , “Your son is here ,” she told the old man. The old man could hardly  1 the young soldier clearly. He reached out his 2 .The soldier held the old man’s hand. The nurse brought a chair so that he could sit  3 the bed. All through the night, the young soldier sat there   4  the old man’s hand. Now and then he heard him say a few words. The dying man said . He only held his son’s hand tightly all through the night.
The next morning, the old man died. The soldier freed his hand and went to  6  the nurse .While the nurse did  7 she had to do, he waited. Then he asked her, “Who was that man?”
The nurse was  8“Wasn’t he your father?” she said.
“No, he wasn’t”, the soldier answered.” I 9 saw him before.”
“Then  10 didn’t you say anything when I took you to  11 ?”
“I knew right away there had been a  12 , and I also knew he needed his son ,_13  his son just wasn’t here. When I found that he was too  14 to tell whether or not I was his son, I knew  15 he needed me, I stayed.
小题1:
A.seeB.lookC.sawD.seeing
小题2:
A.headB.footC.handD.hair
小题3:
A.besidesB.besideC.underD.on
小题4:
A.heldB.holdsC.holdingD.was holding
小题5:
A.everythingB.nothingC.anythingD.something
小题6:
A.cryB.speakC.tellD.say
小题7:
A.howB.whoC.whatD.when
小题8:
A.surprisingB.surprisedC.surpriseD.surprises
小题9:
A.sometimesB.usuallyC.alwaysD.never
小题10:
A.whereB.whyC.whichD.who
小题11:
A.himB.heC.hisD.her
小题12:
A.bedB.chairC.mistakeD.hand
小题13:
A.andB.orC.butD.then
小题14:
A.sickB.healthyC.strongD.nice
小题15:
A.how manyB.how longC.how muchD.how old
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瑜伽冥想的作用?

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下列词语中,没有错别字的一项是(   )

A.迤逦祈祷栗米怏怏不乐

B.酒撰怂恿陶冶钟鸣鼎食

C.穹宇泅水糍粑物华天宝

D.尘芥沽酒愁怅天理昭然

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患者,男,43岁,因胃溃疡行胃大部切除术,术后切口血肿,但尚未化脓,则该病人的切口为()。

A.Ⅰ类切口/丙级愈合

B.Ⅱ类切口/乙级愈合

C.Ⅱ类切口/丙级愈合

D.Ⅲ类切口/乙级愈合

E.Ⅲ类切口/丙级愈合

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小叶性肺炎常见于_______、_______、________者。

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