深刻掌握速度·平均速度是学好物理的基本功

• 作 者: 陈晓庆
• 机 构: 江苏省如皋白蒲高级中学,
• 出 处: 数理化解题研究(高中版)
• 发表日期: 2004年期
• 关键词: 变速直线运动 即时速度 秒末 匀速直线 难于理解 数学式 相似三角形 甲车 千米/小时 函数关系

一、建立速度概念在高中一年级学到变速直线运动的时候,对于即时速度这个概念是比较难于理解的.因为变速运动中的即时速度实际就是时间△t无限减少时平均速度的极限值(用数学式表示v=(?)△s/△t),而这样的意义是学生所不容易接受的.但即时速度在学习变速运动中却占有特别重要的意义,如我们以后学初速、末速以及加速度等概念,都是建立在即时速度这个概念上,我们一定要了解清楚.要达到这个目的,在学即时速度以

First, the establishment of the concept of speed In the first grade of high school to learn the variable speed linear motion, the concept of instantaneous speed is more difficult to understand.Because the instantaneous speed of variable speed motion is actually the limit of the average speed when △ t decreases infinitely Mathematical formula that v = (△) △ s / △ t), and the meaning is not easy to accept students, but the instantaneous speed in learning variable speed movement has a particularly important significance, as we learn after the initial velocity, the final velocity As well as the concept of acceleration, are based on the concept of instant speed, we must understand clearly.To achieve this goal, to learn instant speed