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问题 实验题

阅读短文并解答下列问题.

透镜焦度和度数

透镜焦距f的长短标志着折光本领的大小，焦距越短，折光本领越大.通常把透镜焦距的倒数叫做透镜的焦度，用Φ表示，即Φ=1/f.如果某透镜的焦距是0.5m，它的焦度就是Φ=1/0.5m=2m-1，而平时说的眼镜片的度数就是镜片的透镜焦度乘100的值，例如，400度远视镜片的透镜焦度是4m-1，它的焦距是0.25m.通常远视镜片的度数是正数，而近视镜片的度数是负数.

（1）如图所示是吴翔的眼睛看物体时的成像情况，则吴翔的眼睛是________（近视眼/远视眼），需要佩戴________（凹透镜/凸透镜）来矫正；

（2）若吴翔所戴眼镜镜片的焦距为0.2m，该镜片的焦度为____m-1，度数为____度.

答案

（1）近视眼 凹透镜 （2）5  -500

解决此题要知道：近视眼能看清近处的物体，不能看清远处的物体；近视眼是由于晶状体太厚，使像成在视网膜的前方，要戴一个凹透镜来矫正，戴上凹透镜能使像成在视网膜上；透镜焦距的倒数叫做透镜的焦度，眼镜片的度数，就是镜片的透镜焦度乘100的值；

远视镜片的度数是正数，近视镜片的度数是负数．

解：（1）由图可知，远处物体成像在视网膜前面，所以患的是近视眼，近视眼是由于晶状体曲度变大，会聚能力增强，即折光能力增强，应佩戴发散透镜，使光线推迟会聚；

（2）因为焦度，此透镜的焦距是0.2m，它的焦度Φ=5m-1；

故其镜片的度数为5×100=500度；

完形填空
In the middle of the night, Peter's wife suddenly fell ill. She couldn’t help crying,“Oh, my stomach (胃)! Get the      !”
Peter, awaking from a deep sleep, thought his wife was only having a       dream.
“Stop that noise.” he said to her. He turned over and tried to go to        again, but his wife still cried out, “Oh, help! Help! I'm sure I'm       !”
Peter got out of bed and started       , but he could not find him any clothes.
“Where is my shirt?” he asked. His wife was       ill to tell him, and she could only cry, “Oh, my        stomach!”
As soon as he had put his clothes       , he said, “Now, my dear, are you quite 44that you need the doctor? Surely you can wait       morning, can't you?”
“No, I can't. Go, go, go.” his wife shouted,“       you will find me dead       the morning.”
So Peter went out into the dark street. He had only gone a few meters      he heard his wife calling him again.
“I'm       again now, and I shall not want the doctor.” she said softly.
Hearing this, he started running as       as he could towards the doctor's. When he arrived there, he knocked at the door loudly enough to wake       around.
The doctor put his sleepy head out of the bedroom window and said, “Er? Who's there?”
“Oh, Doctor.”Peter said to him, “I've very       news for you. My wife       ill with a terrible stomachache (胃疼). I was on my way to bring you to her, but she called me back to say the trouble had suddenly       her. So you need not come. Go back to       now, and sleep well!”
小题1:
A．driverB．nurseC．doctorD．child
小题2:
A．terribleB．interestingC．SurprisingD．wonderful
小题3:
A．bedB．sleepC．dreamD．hospital
小题4:
A．walkingB．dyingC．achingD．sleeping
小题5:
A．dressingB．wearingC．raisingD．working
小题6:
A．veryB．soC．tooD．quite
小题7:
A．goodB．badC．wrongD．poor
小题8:
A．downB．offC．onD．up
小题9:
A．surprisedB．afraidC．certainD．worried
小题10:
A．beforeB．forC．toD．until
小题11:
A．AndB．ButC．SoD．Or
小题12:
A．afterB．inC．beforeD．until
小题13:
A．afterB．whenC．beforeD．while
小题14:
A．goodB．wrongC．all rightD．right
小题15:
A．fastB．slowlyC．hurriedlyD．happily
小题16:
A．everyoneB．someoneC．no oneD．doctors
小题17:
A．goodB．badC．necessaryD．ill
小题18:
A．fellB．stayedC．grewD．failed
小题19:
A．goneB．missedC．disappearedD．left
小题20:
A．your homeB．your bedroomC．your dreamD．bed
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选择题

中国、日本位于亚洲的（　　）

A．东亚

B．东南亚

C．北亚

D．南亚
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