知识老人

"Knowledge Elder" is an animated film produced by the Shanghai Science and Education Film Studio in 1994. The knowledgeable elder tells the children: In thunderstorm clouds, lightning and thunder are generated when positive and negative electric charges collide. Our ancestors began using various lightning protection devices over a thousand years ago. While lightning and thunder bring trouble and disasters to people, they also provide humanity with ample water and nitrogen fertilizers, among other benefits.