Bridging British Education Virtual Academy

1. Course Basic Information 1. 课程基本信息

Course Name: A level Physics 课程名称： A-level 物理

Topic: Electrical Properties of Materials and Circuit Analysis (Semiconductors, Internal Resistance, Kirchhoff's Laws) 主题： 材料的电学特性和电路分析 (半导体、内阻、基尔霍夫定律)

Date: December 17 日期： 12月17日

Student: Jackson 学生： Jackson

Teaching Focus 教学重点

Reviewing the behavior of semiconductors (thermistors, LDRs), mastering potential divider calculations, and applying Kirchhoff's Laws to complex circuits.

复习半导体特性（热敏电阻、光敏电阻），掌握分压器计算，并应用基尔霍夫定律分析复杂电路。

Teaching Objectives 教学目标

Differentiate the resistance change with temperature/light in metallic conductors versus semiconductors. 区分金属导体和半导体在温度/光照变化时电阻的变化特性。
Accurately apply the potential divider equation to find unknown voltages or currents. 准确应用分压器公式来求解未知电压或电流。
Recall and apply Kirchhoff's First Law (Junction Rule) and Second Law (Loop Rule) to solve circuit problems. 回忆并应用基尔霍夫第一定律（节点定律）和第二定律（回路定律）来解决电路问题。

2. Course Content Overview 2. 课程内容概览

Main Teaching Activities and Time Allocation 主要教学活动和时间分配

Semiconductors vs. Conductors: Discussed resistance change in copper wire upon heating vs. thermistors/LDRs (negative temperature/light coefficient).

半导体与导体的对比： 讨论了加热时铜线电阻的变化与热敏电阻/光敏电阻（负温度/光系数）电阻的变化。

Potential Divider Circuits Practice: Practiced calculating output voltage and current using the potential divider formula (emphasis on memorizing the formula).

分压器电路练习： 练习使用分压器公式计算输出电压和电流（强调记忆公式）。

Internal Resistance Calculations: Solved problems involving internal resistance using E = IR + r, including complex parallel circuits and interpreting V-I graphs.

内阻计算： 使用 E = IR + r 求解涉及内阻的问题，包括复杂并联电路和 V-I 图的解释。

Kirchhoff's Laws Introduction: Introduction to Kirchhoff's First (charge conservation) and Second (energy conservation) Laws, followed by simple and complex circuit applications involving EMF subtraction.

基尔霍夫定律介绍： 介绍了基尔霍夫第一定律（电荷守恒）和第二定律（能量守恒），随后对涉及 EMF 相减的简单和复杂电路进行了应用练习。

Language Knowledge and Skills 语言知识与技能

Vocabulary:
Semiconductor, Metallic conductor, Thermistor, Light Dependent Resistor (LDR), Negative Temperature Coefficient, Negative Light Coefficient, Potential Divider, Internal Resistance (r), Electromotive Force (EMF, E), Kirchhoff's Laws, Junction, Gradient.

词汇：
半导体, 金属导体, 热敏电阻, 光敏电阻 (LDR), 负温度系数, 负光系数, 分压器, 内阻 (r), 电动势 (EMF, E), 基尔霍夫定律, 节点, 斜率。

Concepts:
Resistance dependence on temperature/light in semiconductors; Potential Divider formula; Internal resistance from V-I graph (EMF = V-intercept, r = -gradient); Kirchhoff's First Law (sum of currents at junction = 0); Kirchhoff's Second Law (sum of EMFs = sum of IR drops).

概念：
半导体电阻对温度/光照的依赖性；分压器公式；从 V-I 图确定内阻（EMF = V轴截距，r = -斜率）；基尔霍夫第一定律（节点电流之和为零）；基尔霍夫第二定律（EMF总和 = IR 压降总和）。

Skills Practiced:
Application of formulae, algebraic manipulation in circuit solving, interpreting graphical data (V-I plots), logical application of circuit laws (Kirchhoff).

练习技能：
公式应用，电路求解中的代数运算，解释图表数据（V-I 图），电路定律的逻辑应用（基尔霍夫）。

Teaching Resources and Materials 教学资源与材料

Whiteboard examples and problem set targeting internal resistance and Kirchhoff's Laws. 针对内阻和基尔霍夫定律的白板示例和习题集。
V-I graph for internal resistance experiment analysis. 用于分析内阻实验的 V-I 图。

3. Student Performance Assessment (Jackson) 3. 学生表现评估 (Jackson)

Participation and Activeness 参与度和积极性

Jackson actively answered conceptual questions about semiconductor behavior and recalled relevant laws. Jackson 积极回答了关于半导体行为的概念性问题并回忆起相关定律。
He showed good initial recall of the potential divider formula but needed reminders on specific application steps. 他对分压器公式有良好的初步记忆，但在具体应用步骤上需要提醒。

Language Comprehension and Mastery 语言理解和掌握

Strong understanding of the difference between metallic conductors and semiconductors regarding thermal/optical effects. 对金属导体和半导体在热/光学效应方面的差异有深刻理解。
Successfully identified the need to subtract EMFs in the anti-parallel cell configuration. 成功识别出在反向串联电池组中需要相减 EMF 的情况。

Language Output Ability 语言输出能力

Oral: 口语：

Responses were clear when explaining physical principles, but occasionally hesitated when structuring multi-step calculations. 在解释物理原理时回答清晰，但在构建多步骤计算时偶尔会犹豫。
Pronunciation is generally good; focused on clarity when stating scientific terms. 发音总体良好；在陈述科学术语时注重清晰度。

Written: 书面：

Showed correct process in several numerical problems, especially in the calculation of current from found voltages in potential divider problems. Required guidance on correctly reading scales on provided graphs (milliamp conversion).

在几个数值问题中展示了正确的解题过程，特别是在分压器问题中从已求电压计算电流。在正确读取所提供图表刻度（毫安转换）方面需要指导。

Student's Strengths 学生的优势

Excellent recall of definitions for Kirchhoff's Laws (Conservation of Charge/Energy). 对基尔霍夫定律（电荷守恒/能量守恒）的定义记忆出色。
Understands the graphical method for determining internal resistance (EMF as y-intercept, r as negative gradient). 理解通过 V-I 图确定内阻的方法（EMF 为 y 轴截距，r 为负斜率）。
Good conceptual grasp of why semiconductors behave differently from metals. 对半导体与金属行为不同的原因有很好的概念理解。

Areas for Improvement 需要改进的方面

Need consistent practice in reading graph axes carefully, especially converting units (e.g., mA to A) for final answers. 需要持续练习仔细读取图表轴，特别是将单位（例如，mA 转换为 A）用于最终答案。
Need to build confidence and speed in setting up simultaneous equations for complex Kirchhoff's Law problems. 需要建立信心和速度来为复杂的基尔霍夫定律问题建立联立方程。
Must memorize the potential divider equation as it is not provided in the exam. 必须记住分压器公式，因为它不在考试中提供。

4. Teaching Reflection 4. 教学反思

Effectiveness of Teaching Methods 教学方法的有效性

Highly effective in linking concepts (e.g., LDR/photoelectric effect, thermistor/freeing electrons). 在关联概念方面非常有效（例如，LDR/光电效应，热敏电阻/电子释放）。
Effective transition from direct application (potential dividers) to complex analysis (Kirchhoff's Laws). 从直接应用（分压器）到复杂分析（基尔霍夫定律）的过渡有效。

Teaching Pace and Time Management 教学节奏和时间管理

The pace was appropriate, allowing thorough coverage of internal resistance analysis before introducing the more complex Kirchhoff's Laws. 节奏合适，允许在引入更复杂的基尔霍夫定律之前彻底涵盖内阻分析。
The teacher managed time well, ensuring Jackson attempted practice questions immediately after concept introduction. 教师很好地管理了时间，确保 Jackson 在概念介绍后立即尝试练习题。

Classroom Interaction and Atmosphere 课堂互动和氛围

Supportive and encouraging, with the teacher providing immediate positive reinforcement and clear remediation for calculation errors.

支持性和鼓励性，教师提供即时的积极强化和对计算错误的明确纠正。

Achievement of Teaching Objectives 教学目标的达成

Objective 1 (Semiconductor difference) achieved well through discussion. 目标1（半导体差异）通过讨论取得了很好的成果。
Objective 2 (Potential Divider) partially achieved; calculation practice was strong, but formula memorization needs reinforcing. 目标2（分压器）部分实现；计算练习很扎实，但公式记忆需要加强。
Objective 3 (Kirchhoff's Laws) introduced successfully, setting the stage for mastery in the next session. 目标3（基尔霍夫定律）介绍成功，为下一节课的掌握奠定了基础。

5. Subsequent Teaching Suggestions 5. 后续教学建议

Teaching Strengths 教学优势

Identified Strengths: 识别的优势：

Excellent use of analogies (e.g., conveyor belt for electron flow). 出色地运用类比（例如，机场传送带比喻电子流动）。
Clear explanation on when and why to subtract EMFs in complex series circuits. 清晰解释了在复杂串联电路中何时以及为何要相减电动势。

Effective Methods: 有效方法：

Immediate correction and guided practice on numerical problems to ensure procedural accuracy. 对数值问题进行即时更正和指导性练习，以确保程序准确性。
Connecting graph analysis (V-I curve) directly back to the governing equations (y=mx+c). 将图表分析 (V-I 曲线) 直接与控制方程 (y=mx+c) 联系起来。

Positive Feedback: 正面反馈：

Teacher praised Jackson for correctly recalling the relationship between EMF, V, and r from the graph analysis. 老师表扬 Jackson 成功回忆起从图表分析中得出的 EMF、V 和 r 之间的关系。

Next Teaching Focus 下一步教学重点

Mastering complex multi-loop circuit analysis using Kirchhoff's Laws. 掌握使用基尔霍夫定律分析复杂多回路电路。

Specific Suggestions for Student's Needs 针对学生需求的具体建议

Calculation & Formula Recall: 计算与公式记忆：

Memorize the potential divider formula: V_out = R2 / (R1 + R2) * V_in. Practice deriving current from this. 必须记住分压器公式：V_out = R2 / (R1 + R2) * V_in。练习如何从该公式推导出电流。
Practice reading graph scales precisely, especially paying attention to prefixes like 'milli' (10^-3) when determining gradient. 练习精确读取图表刻度，特别是在确定斜率时要注意前缀，如 '毫' (10^-3)。

Complex Circuit Analysis (Kirchhoff): 复杂电路分析 (基尔霍夫)：

For Kirchhoff's Loop Rule, establish a consistent clockwise direction for checking EMF signs (sum of EMFs = sum of IRs). 对于基尔霍夫回路定律，建立一致的顺时针方向来检查 EMF 的符号（EMF 总和 = IR 降总和）。
Practice setting up two simultaneous equations derived from the junction rule (I1 = I2 + I3) and the loop rule. 练习建立由节点定律 (I1 = I2 + I3) 和回路定律导出的两个联立方程。

Recommended Supplementary Learning Resources or Homework 推荐的补充学习资源或家庭作业

Complete Question 5 from the handout involving two parallel branches and internal resistance, focusing on setting up the equations correctly. 完成讲义中的第 5 题，该题涉及两个并联支路和内阻，重点是正确建立方程。
Review the difference between Paper 1 (Mechanics/Electricity) and Paper 2 (Materials/Waves) topics. 复习试卷 1（力学/电学）和试卷 2（材料/波）主题之间的区别。