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高中教学和学习过程中有必要探究汽车的曲线运动。这一点也必将作为高考考查的一个热点部分,例如2013年全国统一考试(新课标Ⅱ卷)理综测试的21题考查的就是这类问题。道路上的曲线可分为平曲线(即平时我们所说的弯道)、竖曲线(有凸形竖曲线和凹形竖曲线)和组合型曲线。为了便于高中阶段师生探究,我们将道路的曲线理想简化处理。1.关于汽车过平曲线道路(汽车转弯)时的讨论:问题1:在水平公路上行驶的汽车,转弯时有什么样的潜在危险?如何避免?分析:在水平公路上行驶的汽车在水平公路上行驶的汽车,转弯时所需的向心力mv2/r,只能由车轮与路面间的静摩擦力f1提供的,即f1=mv2/r,因为静摩擦力f最大不能超过最大静摩擦力,当
High school teaching and learning process is necessary to explore the car’s curve movement. This point will certainly serve as a hot spot for college entrance examination examinations. For example, the 21 exams of the 2013 National Unified Examination (New Curriculum, Volume II) comprehensive examinations examine such problems. The curves on the road can be divided into flat curves (that is, the curves we usually refer to), vertical curves (convex vertical curves and concave vertical curves) and combined curves. In order to facilitate high school teachers and students to explore, we will simplify the curve of the road to simplify treatment. 1. Discussion on Car Curve Curves (Turn Car): Q1: What are the potential dangers of turning a car on a horizontal road? How to avoid it? Analysis: A car driving on a level road is on the level Car driving on the road, the required centripetal force when turning mv2 / r, can only be provided by the static friction f1 between the wheel and the road, that is f1 = mv2 / r, because the maximum static friction f can not exceed the maximum static friction, when