Imaginewhatyoucoulddowithamachinethatcouldmakethingsdis...
问题详情：
Imagine what you could do with a machine that could make things disappear.
36 In the books of J.R.R. Tolkein, Bilbo Baggins finds a ring that can make him disappear. Of course, there’s also poor Harry Potter, who used his invisibility cloak (隐形斗篷)to hide from danger.
Now that you’ve got some ideas, it’s time for the hard part: building the cloak. 37 An invisibility cloak has to cheat anything or anyone who might be watching. In order to understand how something can be seen, it’s important to understand how we see.
Human beings can only see objects that reflect light waves. These waves enter the eyes and are then processed by the brain. However, if an object doesn’t reflect light, then the waves don’t enter the eyes, and the brain doesn’t process. 38
Cummer was part of a team of scientists from Duke University, including David Smith and David Schurig, who built the world’s first version of an invisibility cloak. 39 He in May said that an invisibility cloak was possible and Pendry was not the only one thinking about a disappearing act. At the same time, a Scottish physicist, Ulf Leonhardt published a paper on building invisibility equipment.
“It wasn’t easy,” says Cummer. “As often happens in science and research, it didn’t work very well the first time. That first cloak didn’t work like Harry Potter’s — 40 So the research is still under way.”
A. Would you like an invisibility cloak that works just like the one Harry Potter got from his father?
B. The scientists didn’t actually see anything disappear.
C. So building an invisibility cloak is building something that doesn’t reflect light.
D. Researchers in England and the USA have found the materials to build such a cloak.
E. They had been inspired by the work of a British physicist, John Pendry.
F. For inspiration, you could read some books.
G. To do that, you have to give up science fiction and turn to real science.
【回答】
FGCEB
知识点：七选五题型
题型：未分类
