高中英語 學英語,練聽力,上聽力課堂! 注冊 登錄
> 高中英語 > 高中英語閱讀理解 >  內(nèi)容

高考英語閱讀理解(67)

所屬教程:高中英語閱讀理解

瀏覽:

2017年02月22日

手機版
掃描二維碼方便學習和分享
Why do we have in a camera a lens(鏡頭)instead of a simple hole?

The reason can be seen from the figures(圖像).

In Figure 1, the hole is small. Rays of light from a point (P1)outside reach a very small part of the wall opposite, and we see there a small point. But when the hole is bigger, as in Figure 2, rays from the point(P2)can cover a larger part of the wall opposite, and we don’t see a clear point, Rays from other points(Q) outside can also fall on the same place inside. Therefore the picture is not clear when the hole is big and it is not bright when the hole is small because very very little light can pass through it.. We can get better result with a lens. If the lens is made in the shape shown in Figure 3, all the rays of light from the point(P3) are thrown on point(P’) inside. The picture which we see, therefore, is clear, and it is also bright because more light can pass through a lens than through a small hole.

1. In Figure 1 we see a faint small point on the wall because ______.

A. the point(P1) is very small B. the hole isn’t big enough

C. light rays don’t travel in straight lines D. light rays can’t pass through a small hole

2. Figure 2 shows that the bigger the hole is, ______.

A. the more light can pass through B. the clearer the picture will be

C. the better result we will get D. the faster the light rays travel

3. From figure 3, we can see a lens ______.

A. can form a clear picture B. can make light go in a straight line

C. can help light rays to go faster D. cannot give the picture more light than in Fig. 2

4. The main idea of the second paragraph of the article is that ______.

A. a smaller hole is better than a bigger one

B. big holes are better than small ones

C. both a big hole and a small one have their weak points

D. light rays are sure to pass through a hole no matter it is big or small

5. Which of the following statements is true?

A. Light can go through all kinds of materials

B. A camera can’t be made without a lens

C. The lens is only used in a camera

D. Most of the light we get is from the lens



 

答案:1B 2 A 3 A 4 D 5 B
 


用戶搜索

瘋狂英語 英語語法 新概念英語 走遍美國 四級聽力 英語音標 英語入門 發(fā)音 美語 四級 新東方 七年級 賴世雄 zero是什么意思成都市金房匯景新村英語學習交流群

  • 頻道推薦
  • |
  • 全站推薦
  • 推薦下載
  • 網(wǎng)站推薦