题干

为了探究光的反射和折射规律,小名设计并且进行了如图所示的实验:把一束激光从某种玻璃中射向空气,保持入射角不动,改变入射角(每次增加5°),观察反射光线和折射光线的方向变化,并且记录入射角α、反射角β、折射角γ.实验过程中小名发现了一个奇特的现象:当他把入射角增大到45°时发现折射光线突然消失了,把入射角减小为40°时折射光线又出现了.

他以为是实验仪器发生了什么问题,经检查,仪器一切正常.又试了几次,结果还是一样,但又有了新发现:当折射光线消失后反射光线的亮度比有折射光线是时明显增强了.这是怎么一回事呢?小名请教了物理教师.老师告诉他:光从玻璃,水等介质射向空气并且当入射角大于某一个值时确实会发生这种现象,发生这种现象时的入射角叫做临界角λ.听了老师的话,小名产生了浓厚的兴趣,他还想知道:这种玻璃的临界角是多少呢?玻璃和水的临界角相等吗?于是他重新进行了实验(从40°开始,入射角每次增加0.2°).下面是小名的实验数据.

表1光从玻璃射向空气时入射角与反射角、折射角的关系

表2光从水射向空气时入射角与反射角、折射角的关系

仔细考查小名的探究过程和实验数据,回答下列问题:

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阅读下列短文,从每题所给的四个选项(A, B, C和D)中.选出最佳选项.

    Peter loved to shop used articles(物品). Almost a month ago, he bought popular word game that used little pieces of wood with different letters on them. As he was purchasing it, the salesgirl said, “Uh, look, the game box hasn't even been opened yet. That might be worth some money. ”    

    Peter examined the box, and, sure enough, it was completely covered in factory-sealed plastic. And he saw a date of 1973 on the back of the box.       

    “You should put that up for auction (拍卖) on the Internet, and see what happens.” the salesgirl said.       

    “Yes, you're right. People like something rare.” Peter agreed, “I can't imagine there being very many unopened boxes of this game still around 40 years later.”       

    “Don't forget to tell me if you sell it.” the salesgirl smiled.      

    “No problem.” Peter said.       

    After he got home, Peter went online to several auction websites looking for his game. But he couldn't find it. Then he typed in the name of the word game and hit Search. The search result was 543 websites containing information about the changes of the game. Over the years, the game had been produced using letters in different sizes and game boards in different colors. He also found some lists of game fans looking for various versions of the game. Peter emailed some of them, telling them what he had.      

    Two weeks later, Peter went back to the shop.       

    “Hello. Do you still remember the unopened word game?”      

    The salesgirl looked at him for a second, then recognized him and said, “Oh, hi!”

    “I've got something for you,” Peter said. “I sold the game and made $1,000. Thank you for your suggestion.” He handed her three $ 100 bills.       

    “Wow!” the salesgirl cried out. “Thank you, I never expected it.”