داستان سوم ردینگ – سطح ۳
The Fresnel Lens
Grade 3 , 590L
In the early 1800s, navigation was basic. Although ship captains did have some tools to guide them, they still relied heavily on eyesight. This was especially true when they were close to shore. Captains were on constant lookout to make sure their ship didn’t run aground. Lighthouses were constructed to make the shore easier to see. The problem was that lighthouses had weak lights. They could not be seen from far away. This problem was solved by a French physicist named Augustin-Jean Fresnel. Fresnel invented a lens that would focus light into a single source. This focused light could be seen from many miles away.
What conclusion can we make from the information in this passage?
- Fresnel was the greatest inventor of the 19th century.
- Before the Fresnel lens, lighthouses were useless.
- Ship captains had very good eyesight in the 1800s.
- Light can be made more powerful by focusing it.
- Navigation has advanced a lot in the last 100 years.
In the middle of the passage, we learn that before the Fresnel lens, “lighthouses had weak lights.” At the end of the passage, however, we learn that “Fresnel invented a lens that would focus light into a single source. This focused light could be seen from many miles away.” Fresnel’s lens focused light. It could then be seen from many miles away. Using this information, we can understand that focused light must be stronger, or more powerful, than ordinary light. This supports the conclusion that light can be made more powerful by focusing it. Therefore choice (D) is correct.
Although it is reasonable to believe that before the Fresnel lens lighthouses were LESS useful, it is too extreme to suggest that they were useless. Therefore choice (B) is incorrect.
The passage does not provide evidence to support choices (A) and (C). Therefore they are incorrect.
Although it may be true that navigation has advanced a lot in the last 100 years, the passage does not actually provide information to support this conclusion. Therefore choice (E) is incorrect.