题干

张杰和同学在光具座上做“探究凸透镜成像规律”的实验,实验前应调节光屏中心、烛焰中心在凸透镜的____上. 某次实验时三者位置如图所示时,恰能在光屏上得到一个清晰的像,若他把图中蜡烛向左移动4cm,则要想得到清晰的像,需将光屏向____移动,移动距离____(选填“大于”、“等于”或“小于”)4cm;若他把图中蜡烛向右移动4cm,则要想得到清晰的像,光屏移动距离____(选填“大于”、“等于”或“小于”)4cm.

为了探究近视眼和远视眼的成因,张杰和同学制作了液体透镜.当蜡烛、光屏和液体透镜如图放置时,光屏上出现清晰的烛焰像,此像应是____(选填“放大”、“缩小”或“等大”)的.向透镜内注水,光屏上的烛焰像模糊了,若把蜡烛逐渐靠近凸透镜,光屏上的像再次清晰,说明透镜变凸后,成的像将____(选填“靠近”或“远离”)凸透镜.此实验模拟了____(选填“近视”或“远视”)眼的成因.

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主光轴,左,小于,等于,缩小,靠近,近视

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“The first and best of victories for a man is to conquerhimself; to be conquered by himself is, of all things, the most shameful,” saysPlato. Self-control is at the root of all the advantages. Let a man give in tohis impulses (冲动) andfeelings, and from that moment he gives up his moral freedom.

A single angry word has lost many friends. When Socrates foundin himself any temper or anger, he would check it by speaking low in order tocontrol himself. If you are conscious of being angry, keep your mouth shut sothat you can hold back rising anger. Many a person has dropped dead in greatanger. Fits of anger bring fits of disease. “Whoever the gods would destroy,they first make them mad.” “Keep cool,” says Webster, “anger is notargument.” “Be calm in arguing,” says George Herbert, “for fierceness (狂怒) makes error a fault.”

To be angry with a weak man is to prove that you are not strongyourself. “Anger,” says Pythagoras, “begins with foolishness and ends withregret.” You must measure the strength of a man by the power of the feelings heconquers, not by the power of those which conquer him.

Self-control is man’s last and greatest victory.

If a man lacks self-control he seems to lack everything. Withoutit he can have no patience, no power to govern himself; he can have noself-confidence, for he will always be controlled by his strongest feeling. Ifhe lacks self-control, the very backbone and nerve of character are lackingtoo.