Invisibility Ring
Scientists can't yet make an invisibility cloak1 like the one that Harry Potter2 ,for the first time,they’ve constructed a simple cloaking device that makes itself and somethingplaced inside it invisible to microwaves.
When a person "sees" an object,his or her eye senses many different waves of visiblelight as they bounce off the eye and brain then work together to organize thesesensations and reconstruct the object's original shape. So,to make an object invisible,scientists have to keep waves from bouncing off they have to make sure the objectcasts no rwise,the absence of reflected light on one side would give the obiectaway.
Invisibility isn't possible yet with waves of light that the human eye can it is nowpossible with visible light,microwaves are a form of radiant are part of the electromagnetic spectrum,which also includes radio waves,infrared light,ultraviolet rays,X rays,and gamma wavelengths of microwaves are shorter thanthose of radio waves but longer than those of visible light.
The scientists' new "invisibility device" is the size of a drink coaster and shaped like ring is made of a special material with unusual microwaves strike thering,very few bounce off ead,they pass through the ring,which bends the waves allthe way around until they reach the opposite waves then return to their originalpaths.
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.
When the researchers put a small cdpper loop inside the ring,it,too,is nearly invisible. However,the cloaking device and anything inside it do cast a pale the deviceworks only for microwaves,not for visible light or any kind of electromagnetic ,Harry Potter's invisibility cloak doesn’t have any real competition yet.
詞彙：
invisibility/invizE5biliti/n.看不見,無形 spectrum/5spektrEm/n.光譜
cloak/klEuk/斗篷,披風 infrared/5infrE5red/adj.紅外線的
microwave/5maikrEuweiv/n.微波 ultraviolet ray 紫外線
reconstruct/5ri：kEn5strQkt/v.重建 gamma ray 伽馬射線
radiant/5reidjEnt/adj.輻射的 wavelength/5weivleNW/n.波長
electromagnetic/IlektrEJ5mA^nItIk/adj.電磁的coaster/5kEustE(r)/n.托盤,墊子
練習：
y Potter is mentioned in the passage,because scientists
Acan now make an invisible cloak of the same kind as he uses.
Btry to make an invisible cloak of the same kind as he uses.
Ctry to invent a device Similar in idea to the invisible cloak he uses.
Dknow that it is possible to make an invisible cloak of the same kind.
is true of microwaves?
ATheir wavelengths are shorter than those of visible light.
BTheir wavelengths are longer than those of visible light.
CThey are different from visible light as they are a kind of radiant energy.
DThey are visible to the human eye.
is NOT true of the invisibility device?
AIt is made of a special material with unusual ability.
BMicrowaves bounce off it when they strike it.
CMicrowaves pass through it when they strike it.
DIt bends the microwaves all the way around until they reach the opposite
side.
does the word "coaster" mean in the passage?
AA disk or plate placed under a drinking glass to protect a table top.
BA vessel engaged in coastal trade.
CA roller coaster.
DA resident of a coastal area.
y Potter's invisibility cloak doesn’t have any real competition yet,
because
Ascientists have not found out how his cloak works.
Bthe cloaking device is a total failure.
Cthe cloaking device works only for microwaves.
Dthe cloaking device works only for visible light.
答案與題解：
1.C文章的第一段告訴我們,科學家還沒有發明哈里。波特使用的那種隱身衣,所以不能選 A;該段還告訴我們,科學家已製造了,一種裝置,這種裝置能使自身或置於其中的物體不被微波發現,所以C是正確選擇,也就是說,科學家發明的隱形裝置和哈里波特的隱身衣僅僅在概念上相同,這同時說明B和D是錯誤的選擇。
2.B第三段最後一句中告訴我們,A是錯誤選擇,B是正確選擇。該段第三句說,微波與可見光一樣都是一種輻射能,所以C的說法是錯誤的,不能選擇;根據該段第一句：with wavesof light that the human eye can see和第三句：Like visible light,可以得知D是錯誤的說法,也不能選擇。
