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.
双语儿童寓言故事:户外运动Outside Games
双语儿童寓言故事:聪明的乌龟A Smart Tortoise
儿童双语幽默小故事:狼来了Wolf Is Coming
儿童双语幽默小故事:改名字Change Name
儿童双语幽默小故事:安眠药 Sleeping Pills
双语儿童寓言故事:找朋友Look for a Friend
儿童双语幽默小故事:聪明的熊猫A Clever Panda
双语儿童寓言故事:我不能愿意洗澡I Will Not Take a Bath
双语儿童寓言故事:香蕉午餐Bananas for Lunch
双语儿童寓言故事:动物Animals
双语儿童寓言故事:老人和老猫The Old Man and the Old Cat
双语儿童寓言故事:两只猴子Two Little Monkeys
双语儿童寓言故事:我的“公鸡”闹钟My “Cock” Clock
双语儿童寓言故事:大本钟Big Ben
双语儿童寓言故事:国王和他的故事The King and His Stories
双语儿童寓言故事:散步有益It’s Good to Walk
Super Why儿童英语故事动画:小波波Little Bo Peep
双语儿童寓言故事:中国熊猫The Panda in China
儿童双语幽默小故事:好孩子 A Good Boy
儿童双语幽默小故事:牛和狗The Ox and the Dog
双语儿童寓言故事:Spring in the Green Season春天
儿童双语幽默小故事:我没法煮它I can’t Cook It
双语儿童寓言故事:这是不公平It’s Unfair
儿童双语幽默小故事:画蛇添足Adding Feet to a Snake
儿童双语幽默小故事:狼与鹤The Wolf and the Crane
Super Why儿童英语故事动画:侏儒妖怪 Rumplestiltskin
双语儿童寓言故事:一只蚂蚁A Little Ant
双语儿童寓言故事:调皮的猴子naughty Monkey
儿童双语幽默小故事:聪明的国王所罗门The Clever King Solomon
双语儿童寓言故事:聪明的机器人Smart Robot
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