所谓“直柱模型”是指对连续流动的气体、液体及定向运动的电荷群体进行瞬时取样 ,设想它们为流动者的“柱体” ,然后对“柱体”应用相应的物理规律 ,以求得问题的解决例 1　某地强风的风速为v ,设空气密度为ρ ,如果把通过横截面积为S的风的动能全部转化为电能 ,求相应的电功 The so-called “straight-leg model” refers to the instantaneous sampling of continuously flowing gas, liquid, and directed-moving charge groups. It is assumed that they are the “pillars” of the flower, and then apply the corresponding physical laws to the “columns” in order to obtain Solution to Problem 1. Example 1 The wind speed of a strong wind is v, and the air density is ρ. If the kinetic energy of the wind passing through the cross-sectional area S is converted into electric energy, the corresponding electric power is obtained.