Scientists cant yet make an invisibility cloak1 like the one that Harry Potter2 uses.But,for the first time,theyve constructed a simple cloaking device that makes itself and somethingplaced inside it invisible to microwaves.
Invisibility isnt possible yet with waves of light that the human eye can see.But it is nowpossible with microwaves.Like visible light,microwaves are a form of radiant energy.Theyare part of the electromagnetic spectrum,which also includes radio waves,infrared light,ultraviolet rays,X rays,and gamma rays.The wavelengths of microwaves are shorter thanthose of radio waves but longer than those of visible light.
To a detector set up to receive microwaves on the other side of the ring,it looks as if thewaves never changed their paths as if there were no object in the way! So,the ring is effectively invisible.
2017届高考英语一轮复习知识点精练:2.5 名词性从句 Section Ⅰ(新人教版含解析)
2017届高考英语一轮语法复习课件:7 动词时态(牛津译林版)
2017届高考英语大一轮全册复习课件:M8U2《The universal language》(牛津译林版)
2017届高考英语大一轮全册复习课件:M4U2《Sporting events》(牛津译林版)
2017届高考英语一轮复习知识点精练:2.1 冠词 Sectiont Ⅱ(新人教版含解析)
2017届高考英语一轮复习知识点精练:2.2 代词和介词(短语) Sectiont Ⅱ(新人教版含解析)
2017届高考英语大一轮全册复习课件:M3U2《Language》(牛津译林版)
2017届高考英语一轮语法复习课件:1 名词和冠词(牛津译林版)
2017届高考英语大一轮全册复习课件:M6U1《Laughter is good for you》(牛津译林版)
2017届高考英语一轮复习考点集训课件:10 非谓语动词(Ⅰ)(牛津译林版)
2017届高考英语一轮复习考点集训:7 动词时态(Ⅲ)(牛津译林版含答案)
2017届高考英语大一轮全册复习课件:M2U1《Tales of the unexplained》(牛津译林版)
2017届高考英语一轮语法复习课件:9 主谓一致(牛津译林版)
2017届高考英语大一轮全册复习课件:M4U1《Advertising》(牛津译林版)
2017届高考英语大一轮全册复习课件:M1U2《Growing pains》(牛津译林版)
2017届高考英语一轮复习知识点精练:2.3 情态动词和虚拟语气 Section Ⅰ(新人教版含解析)
2017届高考英语一轮语法复习课件:8 被动语态(牛津译林版)
2017届高考英语大一轮全册复习课件:M7U4《Public transport》(牛津译林版)
2017届高考英语一轮复习知识点精练:2.1 冠词 Section Ⅰ(新人教版含解析)
2017届高考英语大一轮全册复习课件:M6U2《What is happiness to you》(牛津译林版)
2017届高考英语大一轮全册复习课件:M5U3《Science versus nature》(牛津译林版)
2017届高考英语一轮语法复习课件:11 虚拟语气(牛津译林版)
2017届高考英语大一轮全册复习课件:M4U3《Tomorrow’s World》(牛津译林版)
2017届高考英语一轮复习演练:1.5《A Lesson in a La》(外研版含解析)
2017届高考英语一轮语法复习课件:6 短语动词(牛津译林版)
2017届高考英语一轮语法复习课件:5 情态动词(牛津译林版)
2017届高考英语一轮语法复习课件:15 定语从句(牛津译林版)
2017届高考英语一轮复习知识点精练:2.2 代词和介词(短语) Section Ⅰ(新人教版含解析)
2017届高考英语大一轮全册复习课件:M2U2《Wish you were here》(牛津译林版)
2017届高考英语一轮语法复习课件:12 句子的类型(牛津译林版)
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