探究合外力做功和物体动能变化的关系

探究合外力做功和物体动能变化的关系 《探究合外力做功和物体动能变化的关系》 教 学 案 例 北京师范大学南山附属学校 王艳丽 二00六年十月 dynamic publicity, timely reports on the rectification work achieved success, and create the experience, the emergence of a typical, timely exposure health corner, management of the blind spot, "filthy" phenomenon and buck passing, not as a phenomenon. The area units and responsible departments to use the blackboard newspaper, publicity column, publicity car, understand the paper, literature and art programs, promote the remediation work in the state organs, into the community, into the enterprise, into the school, family, and strive to create the city's mobilization, the people, the whole society Will be involved in a strong atmosphere. To strengthen supervision and security. The command department performance steering group to be in accordance with the municipal Party committee, municipal government of accountability measures, supervision and inspection plan formulation, implementation of "rectification process tracking supervision, remediation regular notification system, the supervision throughout the entire process of remediation work. Do not attach importance to, not as, sluggish, pull the hind legs of the city's local and departmental units to give notice of criticism until the start the administrative accountability procedures. Fifth, we must strengthen the security assessment. Command assessment group to effectively improve the intensify of the assessment, according to the acceptance and effectiveness of supervision, for all districts and counties, departments directly under 《探究合外力做功和物体动能变化的关系》教学案例 北师大南山附中 王艳丽 设计 领导形象设计圆作业设计ao工艺污水处理厂设计附属工程施工组织设计清扫机器人结构设计 思想: 学生的发展具有阶段性，高 一年级 小学一年级数学20以内加减练习题小学一年级数学20以内练习题小学一年级上册语文教学计划人教版一年级上册语文教学计划新人教版一年级上册语文教学计划 学生的认知能力正处于由具体形象思维向抽象逻辑思维过渡阶段，在这一时期教师应尽量多地将书本知识与实际生活密切联系起来，争取以教学知识为载体帮助学生稳步实现这一过渡。 本节课开篇播放了四段学生熟悉的生活录像，目的是使学生通过观察了解合外力对物体做功与物体动能变化之间的定性关系。同时可以激发学生的学习兴趣，实现将物理生活化、将生活物理化的另一教学目标。这也顺应了新课标关于增强学生创新意识和实践能力，发展学生探索自然、理解自然的兴趣与热情的要求。 儿童的发展自始至终都是一种儿童主体的自我调节活动。外界的环境刺激，只有被主体选择，成为主体的反应对象时才会对主体的发展产生影响，所以在本节课所有的教学环节中都贯穿着以学生为主体的教学思想。考虑到高一学生的思维活跃但动手能力尚需锻炼的特点，在实验探究环节我设计成先让学生发散思维大胆设计然后根据身边条件选择易于操作、误差较小的实验方案进行实验。使得学生自始至终都能够积极参与，并且在活动的过程中体验到成功的快乐～ 在做完实验之后我又设计了一个利用已有知识对动能定理进行推导的环节，一方面培养了学生的抽象逻辑思维，另一方面也实现了对力学知识体系再认识的一次理论升华，同时对学生解决问题的方法也有一定的指导意义。 《课标》要求、教学内容及教学对象的大体 分析 定性数据统计分析pdf销售业绩分析模板建筑结构震害分析销售进度分析表京东商城竞争战略分析 : 新课标要求“通过实验，探究恒力做功与物体动能变化的关系，理解动能和动能定理。用动能定理理解生活和生产中的现象。”具体操作为“用打点计时器或光电计时器探究恒力做功与物体动能变化的关系。”和“从牛顿第二定律导出动能定理。” 《探究合外力做功和物体动能变化的关系》属于广东版高中物理(必修2)第四章第三节内容。教材要求在本节中 (1) 要突出实验探究，使学生经历和体验科学探究的方法;(2)重视学生的自主学习;(3)重视对学生的理性思维的训练。根据课标要求本节教材创造性地采用了实验探究的方法定量地研究外力对物体做功与物体动能的变化关系，然后从理论上进行推导，最后归纳得出结论。 高一年级学生在刚开始学习高中物理时由于抽象思维刚刚起步所以容易产生畏难情绪，采取由浅入深、由定性到定量的教学策略可以帮助学生克服畏难情绪。而且采用多样化教学模式可以充分调动学生学习的积极性，培养学生的合作dynamic publicity, timely reports on the rectification work achieved success, and create the experience, the emergence of a typical, timely exposure health corner, management of the blind spot, "filthy" phenomenon and buck passing, not as a phenomenon. The area units and responsible departments to use the blackboard newspaper, publicity column, publicity car, understand the paper, literature and art programs, promote the remediation work in the state organs, into the community, into the enterprise, into the school, family, and strive to create the city's mobilization, the people, the whole society Will be involved in a strong atmosphere. To strengthen supervision and security. The command department performance steering group to be in accordance with the municipal Party committee, municipal government of accountability measures, supervision and inspection plan formulation, implementation of "rectification process tracking supervision, remediation regular notification system, the supervision throughout the entire process of remediation work. Do not attach importance to, not as, sluggish, pull the hind legs of the city's local and departmental units to give notice of criticism until the start the administrative accountability procedures. Fifth, we must strengthen the security assessment. Command assessment group to effectively improve the intensify of the assessment, according to the acceptance and effectiveness of supervision, for all districts and counties, departments directly under 精神、探究意识。适度的理性思维训练也会使学生体会科学探究、科学研究的方法。 教学目标: 1、知识与技能 (1) 知道外力对物体做功可以改变物体的动能。 (2) 理解动能定理，知道动能定理的使用条件，会用动能定理进行计算。 (3) 能设计并会利用实验进行探究物理规律。 (4) 能用学过的知识进行理论推导。 (5) 会用动能定理解决力学问题，知道规范解题的一般步骤。 2、过程与方法 (1) 经历探究的主要环节，通过实验设计、观察实验现象、 记录 混凝土 养护记录下载土方回填监理旁站记录免费下载集备记录下载集备记录下载集备记录下载 和处理实 验数据，通过分析、比较、归纳得出实验结果，通过理论分析、推导 与论证，得到外力做功与物体动能变化的关系，体会科学探究的方法。 (2) 通过理论分析与论证的过程，使学生受到理性思维的训练。 3) 通过理论应用使学生灵活迁移所学知识解决实际问题。 ( 3、情感、态度与价值观 (1) 通过实验与探究，培养学生的探究意识和动手实践能力。 (2) 经历讨论与交流，培养学生的语言表述能力和团结合作的学习精神。 (3) 通过理论应用，培养学生对知识的迁移和应用能力。 教学重点难点及资源准备: 实验探究恒力做功与动能变化之间的关系及动能定理是本节课的重点。利用牛顿第二定律推导动能定理是本节课的难点。 教学资源有:多媒体方面有四段录像片段、PowerPoint 课件 超市陈列培训课件免费下载搭石ppt课件免费下载公安保密教育课件下载病媒生物防治课件 可下载高中数学必修四课件打包下载 ，分组用实验器材有电火花打点计时器、重锤、纸带、刻度尺等。 教学过程: 课题引入: 教师:观看录像，定性说出合外力对物体做功，物体动能发生怎样的变化, (播放四段录像指导学生关注观察对象，分析合外力对物体做功会引起物 体动能发生怎样的变化,) 教师给出幻灯片:合外力对物体做正功，物体动能( )。合外力对物体 做负功，物体动能 ( )。 dynamic publicity, timely reports on the rectification work achieved success, and create the experience, the emergence of a typical, timely exposure health corner, management of the blind spot, "filthy" phenomenon and buck passing, not as a phenomenon. The area units and responsible departments to use the blackboard newspaper, publicity column, publicity car, understand the paper, literature and art programs, promote the remediation work in the state organs, into the community, into the enterprise, into the school, family, and strive to create the city's mobilization, the people, the whole society Will be involved in a strong atmosphere. To strengthen supervision and security. The command department performance steering group to be in accordance with the municipal Party committee, municipal government of accountability measures, supervision and inspection plan formulation, implementation of "rectification process tracking supervision, remediation regular notification system, the supervision throughout the entire process of remediation work. Do not attach importance to, not as, sluggish, pull the hind legs of the city's local and departmental units to give notice of criticism until the start the administrative accountability procedures. Fifth, we must strengthen the security assessment. Command assessment group to effectively improve the intensify of the assessment, according to the acceptance and effectiveness of supervision, for all districts and counties, departments directly under 学生:合外力对物体做正功，物体动能增加，合外力对物体做负功，物体动能减 少。 教师:那么，合外力对物体所做的功与物体在这一过程中动能的变化定量关系是 怎样的呢, 一、实验设计: 教师:请大家大胆猜想，说出你的想法。 学生:相等;成正比;......... 教师:(打出幻灯片，给出两种观点的公式表达，以方便学生进行下一步的探究 活动)。请大家设计一个实验过程来进行探究。 学生活动:(几人一小组进行讨论交流初步拿出小组方案。) 教师:请说出你的研究方案中的(1)、研究对象;(2)、研究的运动过程;(3)、 你的研究中需要测量哪些数据,(4)、需要哪些测量工具, 师生交流、生生交流。 (学生经过第一步的录像观察，能够比较容易的在生活中找到研究对象。只是在如何测量上会感到有些困难，这时可适度引导提醒他们在实验时可抓主要矛盾设计简单容易操作的方案进行实验。) 教师:按桌面上提供的器材，小组讨论后1、设计一个实验过程来进行探究。2、 设计数据记录表格。3、设计实验步骤。 二、实验操作: 教师给出参考表格、教师进行指导、学生实验操作并记录实验数据。 教师:根据你的实验数据试分析在重锤下落的过程中，重力对重锤所做功与重锤 动能变化之间有什么关系, 学生:基本相等，重力做功值比动能增量略大。 教师:那我们可以得出一个怎样的结论,略大的原因是什么, 学生:重力对重锤所做功基本等于重锤动能变化，略大的原因是在这一过程中有 摩擦力在对重锤做功。 教师:如果将摩擦力的影响考虑进去，应如何描述实验结论, 学生:合外力对物体做功与物体动能变化值相等。 教师:由于我们并没有测量摩擦力，所以这个结论含有猜想的成分。你能否用前 面学过的理论去证明这个结论。 学生活动(可找两至三名学生在黑板前板演。教师对程度略低的学生可给与一定的提示，如帮助他们确定一个易于研究的物理模型等。) 教师根据学生所作的情况进行总结，让学生在交流中体会学习物理的方法与技巧。 dynamic publicity, timely reports on the rectification work achieved success, and create the experience, the emergence of a typical, timely exposure health corner, management of the blind spot, "filthy" phenomenon and buck passing, not as a phenomenon. The area units and responsible departments to use the blackboard newspaper, publicity column, publicity car, understand the paper, literature and art programs, promote the remediation work in the state organs, into the community, into the enterprise, into the school, family, and strive to create the city's mobilization, the people, the whole society Will be involved in a strong atmosphere. To strengthen supervision and security. The command department performance steering group to be in accordance with the municipal Party committee, municipal government of accountability measures, supervision and inspection plan formulation, implementation of "rectification process tracking supervision, remediation regular notification system, the supervision throughout the entire process of remediation work. Do not attach importance to, not as, sluggish, pull the hind legs of the city's local and departmental units to give notice of criticism until the start the administrative accountability procedures. Fifth, we must strengthen the security assessment. Command assessment group to effectively improve the intensify of the assessment, according to the acceptance and effectiveness of supervision, for all districts and counties, departments directly under 教师:我们应用牛顿第二定律导出的这个公式是从功和能量的角度来研究力学问 题的，它的名字叫动能定理，是这一章的重点。同学们在以后的学习中会 逐步体会到它的重要性及优越性。 三、理论应用 例题:质量为m的重球在距地面高为H处自由下落，打入沙坑的深度h。 求沙子对重球的平均阻力f。 四、小结 教师:1、针对同一物理现象，可以从不同角度分析寻找相关的物理规律。 2、动能定理内容: 3、文字表述:合外力对物体所做的功等于物体动能的变化。 4、你还有哪些收获, 学生发言表达自己的体会。 五、布置作业 1、利用理论或实践验证动能定理不仅适用于恒力做功和直线运动，同时也适用变力做功和曲线运动。 2、教科书 74页1、3、6。 教学反思: 本节课我要完成的一个重要任务是让学生认识动能定理。在整体的设计中我贯穿着一个由感性到理性、由定性分析到定量研究再到理论分析的一个教学思想。在这个教学思想的引导下，教学设计按照学生的实际情况结合教学任务设置难度、梯度，使学生敢于向上爬、乐于向上爬～ 开篇的四段生活情景录像使学生耳目一新，原来物理离生活这么近～提出问题后由于是定性结论所以几乎所有学生都能较顺利地完成，实现了学生能够讲物理与生活紧密联系的学习目的，为接下来的实验设计提供了很好的素材。 dynamic publicity, timely reports on the rectification work achieved success, and create the experience, the emergence of a typical, timely exposure health corner, management of the blind spot, "filthy" phenomenon and buck passing, not as a phenomenon. The area units and responsible departments to use the blackboard newspaper, publicity column, publicity car, understand the paper, literature and art programs, promote the remediation work in the state organs, into the community, into the enterprise, into the school, family, and strive to create the city's mobilization, the people, the whole society Will be involved in a strong atmosphere. To strengthen supervision and security. The command department performance steering group to be in accordance with the municipal Party committee, municipal government of accountability measures, supervision and inspection plan formulation, implementation of "rectification process tracking supervision, remediation regular notification system, the supervision throughout the entire process of remediation work. Do not attach importance to, not as, sluggish, pull the hind legs of the city's local and departmental units to give notice of criticism until the start the administrative accountability procedures. Fifth, we must strengthen the security assessment. Command assessment group to effectively improve the intensify of the assessment, according to the acceptance and effectiveness of supervision, for all districts and counties, departments directly under 学生发散式实验设计环节收到的效果很好，学生们想的面很宽，大家共同讨论各个方案的可行性，很大程度地培养了学生的创新思维和发散思维。 为了突出主要矛盾，也为了让学生体验成功的快乐，探究实验按照教材的要求选择了简便易操作的重锤下落问题进行研究。在数据分析时教师注重引导重力做功与物体动能变化量不等的原因，这样不仅培养了学生严谨的科学态度同时也使学生对动能定理有了深刻的理解。 在理论分析论证环节我感到学生还不习惯利用已有信息去推理新信息。也就是思维还有些僵化，不能够多角度分析问题，以为有了牛顿第二定律已经可以解决力学问题了为什么还要在变形再推导动能定理呢?从培养学生科学素养方面这部分的教学显得尤为重要，所以在以后的教学中我将注意寻找机会，在有合适的教学载体的情况下再多进行此方面的引导。 教学流程图: 利用生活情景引入定性讨论问题 归纳结论 创设二次问题情景 启发与再讨论 发散式实验设计 寻找易操作实验方案 分组实验探究 理论分析与论证 理论应用 小结 布 置 作 业 dynamic publicity, timely reports on the rectification work achieved success, and create the experience, the emergence of a typical, timely exposure health corner, management of the blind spot, "filthy" phenomenon and buck passing, not as a phenomenon. The area units and responsible departments to use the blackboard newspaper, publicity column, publicity car, understand the paper, literature and art programs, promote the remediation work in the state organs, into the community, into the enterprise, into the school, family, and strive to create the city's mobilization, the people, the whole society Will be involved in a strong atmosphere. To strengthen supervision and security. The command department performance steering group to be in accordance with the municipal Party committee, municipal government of accountability measures, supervision and inspection plan formulation, implementation of "rectification process tracking supervision, remediation regular notification system, the supervision throughout the entire process of remediation work. Do not attach importance to, not as, sluggish, pull the hind legs of the city's local and departmental units to give notice of criticism until the start the administrative accountability procedures. Fifth, we must strengthen the security assessment. Command assessment group to effectively improve the intensify of the assessment, according to the acceptance and effectiveness of supervision, for all districts and counties, departments directly under