春节联欢晚会里著名魔术师刘谦表演的魔术十分精彩,也引起了很多人的好奇心,特别是镜子里伸出一只胳膊的那段(如左图),简直太神奇了,魔术师是怎样做到的呢,魔术中到底又包含着怎样的物理知识呢?我们知道魔术不是魔法,既然能看见胳膊,就一定有一个人藏在后面,可是看画面,哪里有藏人的地方 The magic performed by Liu Qian, a famous magician at the Spring Festival Gala, is very exciting and has aroused many people’s curiosity, especially the one with an arm outstretched in the mirror (pictured left). It is amazing and the magician is What, then, did the magic contain in the end what kind of physical knowledge? We know magic is not magic, since we can see the arm, there must be a hidden behind, but look at the picture, where the Tibetan people