我们在电视中曾经看到,宇航员在航天器里,只要轻轻一踮脚,人就会腾空而起,在空中飘浮.这奇妙的景象并不是神话,也不是魔术,而是活生生的事实.这是什么原因?原来一切物体在航天飞行时,重量都大大减轻了,这种现象叫“失重”.物体失重,变得很轻, We have seen on television that astronauts in the spacecraft simply slapped feet and people would rise and float in the air. This wonderful sight is not a myth or a magic but a living fact. What is the reason? The weight of all objects in space flight has been greatly reduced. This phenomenon is called “weightlessness.” Objects lose weight and become light.