例1(湖北省)如图1所示漂浮在液面上一个小铁球,光照充足情况下二天后观察小球将＿＿(上浮、下沉、不变)因为＿＿(小球体积变化忽略不计)·解析:本题妙在从题给内容到图示,都“貌不出众”,使同学们易于“下眼看待”,实则其隐含着:在光照充足情况下,植物发生光合作用,产生氧气,铁 Example 1 (Hubei Province) A small iron ball floated on the liquid surface as shown in Fig.1. Two days later, the observation of the ball will be __ (floating, sinking, and invariable) because __ (negligible change in the volume of the ball) ) · Analysis: This topic is wonderful from the subject to the content to the graphic, all of which are “looking out of appearance”, which makes it easy for the students to “look at the eye”. In fact, it implied that: under sufficient light, the plants produce photosynthesis and produce Oxygen, iron