学习凸透镜成像这部分内容时,有一些涉及计算物距、像距或焦距范围的问题,要用到不等式或不等式组.用数学知识解决物理问题,是学好物理的一种重要方法.现举几例进行归类分析.一、判断焦距的范围例1将一支点燃的蜡烛放在距凸透镜20cm处,在光屏上得到一个缩小的像.当蜡烛距凸透镜14cm时,在光屏上得到一个放大的 When learning about this part of lenticular imaging, there are some issues that involve the calculation of object distance, image distance, or focal length range, and inequalities or inequality groups. Using mathematical knowledge to solve physical problems is an important way to learn physics. Example for classification analysis First, determine the scope of the focal length Example 1 A lit candle placed 20cm away from the convex lens, get a diminished image on the screen when the candle away from the convex lens 14cm, get a enlarged