问题 选择题

下列关于光的认识,正确的是(  )

A.光的干涉和衍射不仅说明了光具有波动性,还说明了光是横波

B.拍摄玻璃橱窗内的物品时,往往在镜头前加一个偏振片以增加透射光的强度

C.爱因斯坦提出的光子说否定了光的波动说

D.全息照片往往用激光来拍摄,主要是利用了激光的相干性

答案

A、光的干涉和衍射能说明光具有波动性,不能说明光是一种横波.光的偏振现象才说明了光是一种横波.故A错误.

B、在镜头前加一个偏振片,是为了减弱反射光的强度,并不能增加透射光的强度.故B错误.

C、爱因斯坦提出的光子说并没有否定光的波动说,光子能量公式E=hγ中频率γ就具有波的特征.故C错误.

D、全息照片主要是利用了激光的相干性.故D正确.

故选D

解答题
阅读理解

阅读理解。

阅读下面短文,根据所读内容在答题卡相应番号后横线处填入恰当的单词(注意:每个空格只填一个单词)

     It is easy for many people to catch a cold in the springtime or fall. It makes us wonder if scientists

can send a man to the moon, why can't they find a cure for the common cold? The answer is easy.

There are actually hundreds of kinds of cold viruses out there. You never know which one you will

get, so there isn't a cure for each one.

     When a virus attacks your body, your body works hard to get rid of it. Blood rushes to your nose

and cause a block in it. You feel terrible because you can't breathe well, but your body is actually

eating the virus. Your temperature goes up and you get a fever, but the heat of your body is killing

the virus. You also have a runny nose to stop the virus from getting into your cells. You may feel very

uncomfortable, but actually your wonderful body is doing everything it can to kill the cold.

      Different people do different things to deal with colds. In the United States and some other

countries, for example, people might eat chicken soup to make themselves feel better. Some people

take hot baths and drink warm liquids. Other people take medicine to stop various symptoms (症状)

of colds.

      There is one interesting thing to note -some scientists say taking medicines when you have a cold

is actually bad for you. The virus stays in you longer because your body doesn't have a way to fight it

and kill it. Bodies can do an amazing job on their own. There is a joke, however, on taking medicine

when you have a cold. It goes like this:

     It takes about one week to get over a cold if you don't take medicine, but it takes only seven days

to get over a cold if you take medicine.