[论文解读] Improving Student Understanding of Magnetism

Chandralekha Singh|arXiv (Cornell University)|Jan 6, 2017

Science Education and Pedagogy参考文献 8被引用 4

一句话总结

本研究探讨了在微积分物理课程中学生对磁学的持久误解，采用书面测验、选择题测试和课堂演示访谈等方式。研究发现，学生在理解磁场和磁力的三维矢量特性方面存在困难，尤其是在将预测与实际实验结果进行对比时；同时发现，直觉推理常常压倒理论理解，尤其在实践情境中表现明显。

ABSTRACT

Formally investigating the sources of students' difficulties around specific subjects is crucial for developing appropriate strategies to help students. We have been studying difficulties in understanding magnetism encountered by students in the calculus-based introductory physics courses. A majority of these students are engineering majors. Student difficulties were assessed by administering written free-response questions and by developing and administering a research-based multiple-choice test to students. We also conducted individual interviews with a subset of students. Some of these interviews were lecture-demonstration based interviews in which students were asked to predict the outcomes of experiments, perform the experiments and reconcile the differences between their predictions and observations. Some of the common misconceptions found in magnetism are analogous to those found in electrostatics. Some additional difficulties are due to the non-intuitive three dimensional nature of the relation between magnetic field, magnetic force and velocity of the charged particles or direction of current. Another finding is that students often used their gut feeling and had more difficulty reconciling with the idea that the magnetic force and field are perpendicular to each other when they were shown actual lecture-demonstration setups and asked to predict outcomes of experiments than when they were asked to explain relation between magnetic force and field theoretically solely based upon an equation. We discuss the implications of this research to teaching and learning.

研究动机与目标

• 识别并分析微积分基础物理课程中学生对磁学的持久误解。
• 研究学生的直觉推理在理解磁力、磁场与速度之间垂直关系时如何产生干扰。
• 探讨学生在预测物理实验结果与解决理论问题时的表现差异。
• 评估基于课堂演示的访谈在揭示和解决误解方面的有效性。
• 基于对学生困难的实证研究，为磁学教学提供更有效的教学策略。

提出的方法

• 通过书面自由作答题评估学生对磁学概念理解的程度。
• 开发并实施一项基于研究的多项选择测试，以量化大规模学生群体中的误解情况。
• 对部分学生进行个别访谈，包括在课堂演示中预测、观察并调和实验结果的环节。
• 分析学生的作答和访谈记录，识别误解和推理错误的模式。
• 比较学生在理论问题与动手预测任务中的表现，评估直觉和经验学习的作用。
• 结合定量评估和定性访谈数据，交叉验证学生困难的发现。

实验结果

研究问题

• RQ1 在大学物理入门课程中，学生对磁场和磁力最常见的误解是什么？
• RQ2 学生在理论推理与实际实验演示中预测磁力结果时，其表现有何不同？
• RQ3 直觉推理在多大程度上阻碍了学生将预测与磁学实际实验结果相协调的能力？
• RQ4 磁场、磁力与速度之间的三维矢量关系如何导致学生的误解？
• RQ5 为何学生在观察物理实验时比在解方程时更难理解磁力与磁场的垂直性？

主要发现

• 在微积分物理课程中的多数工程专业学生持有与静电学中类似的磁学误解。
• 学生在理解磁场、磁力和粒子速度的三维矢量特性方面经常遇到困难，导致持续性的概念错误。
• 学生在预测物理实验结果时更倾向于依赖直觉和感觉，尤其是在结果与预期不符时。
• 学生在动手课堂演示中调和预测与观察结果时，比在基于方程的理论问题解决中表现出更大的困难。
• 即使经过理论教学，学生在接触物理装置时仍难以理解磁力、磁场与速度之间的垂直关系。
• 当学生面对真实世界演示时，误解更加根深蒂固，表明在实践情境中直觉推理可能压倒正式知识。