【People's Education Press】High School Physics Elective Compulsory Volume 2

📚 Content Summary

This course is based on the compulsory elective high school physics curriculum, covering advanced electromagnetism topics including Ampere force, Lorentz force, electromagnetic induction, alternating current, and sensors—core physical concepts and laws.

Delve into the mysteries of electromagnetism and master fundamental principles of high school physics.

Author: People's Education Press Curriculum Textbook Research Institute Physics Curriculum Textbook Research and Development Center

Acknowledgments: Approved by the National Textbook Committee Expert Committee (2019)

🎯 Learning Objectives

1. Accurately apply the left-hand rule to determine the direction of Ampere force and Lorentz force, and understand the special case of force direction for negative charges.
2. Master the formula for calculating the magnitude of Lorentz force, and independently derive the formulas for radius and period of circular motion of charged particles in a uniform magnetic field.
3. Analyze and explain the working principles of mass spectrometers, cyclotrons, velocity selectors, and magnetohydrodynamic generators.
4. Accurately state the content of Lenz’s Law and Faraday’s Law of Electromagnetic Induction, and use the right-hand rule to determine the direction of induced current when cutting magnetic field lines.
5. Flexibly apply the formulas E = n \frac{\Delta \Phi}{\Delta t} and E = Blv \sin \theta to calculate induced electromotive force in various physical scenarios.
6. Analyze complex electromagnetic phenomena such as self-inductance, eddy currents, and electromagnetic damping from the perspective of energy conversion, and solve related practical physics problems.
7. Analyze the process by which a coil rotating in a magnetic field generates alternating current, skillfully write instantaneous value expressions, and perform conversions between peak and root mean square (RMS) values.
8. Understand the basic principles of ideal transformers, and use the proportional relationship between voltage and number of turns to solve circuit problems.
9. Comprehend the mechanism of power loss in long-distance power transmission, calculate voltage drop and power loss in transmission lines, and explain the economic advantages of high-voltage transmission.
10. Describe the periodic changes in charge, current, electric field energy, and magnetic field energy in an LC oscillating circuit.

🔹 Lesson 1: Ampere Force and Lorentz Force: The Interaction of Magnetic Fields with Matter

Overview: This lesson explores the physical laws governing the interaction of magnetic fields with macroscopic current-carrying conductors (Ampere force) and microscopic moving charges (Lorentz force). Through studying the left-hand rule, the Lorentz force formula, and the resulting circular motion in a uniform magnetic field, students will grasp the fundamental physical principles behind modern scientific instruments such as mass spectrometers and cyclotrons, and understand the microscopic connection between Ampere force and Lorentz force.

Learning Outcomes:

• Accurately apply the left-hand rule to determine the direction of Ampere force and Lorentz force, and understand the special behavior of force direction for negative charges.
• Master the formula for calculating the magnitude of Lorentz force, and independently derive the formulas for the radius and period of circular motion of charged particles in a uniform magnetic field.
• Analyze and explain the operating principles of mass spectrometers, cyclotrons, velocity selectors, and magnetohydrodynamic generators.

🔹 Lesson 2: Electromagnetic Induction: Principles, Nature, and Applications

Overview: This instructional design covers the core principles and applications of electromagnetic induction. Emphasis is placed on uncovering the essence of Lenz’s Law and Faraday’s Law of Electromagnetic Induction through experimental inquiry, and deeply analyzing the microscopic mechanisms of motional and induced electromotive forces. Additionally, by exploring phenomena such as self-inductance, mutual inductance, eddy currents, and electromagnetic damping, this lesson demonstrates how electromagnetic induction facilitates energy conversion and finds practical application in modern technology.

Learning Outcomes:

• Accurately state the content of Lenz’s Law and Faraday’s Law of Electromagnetic Induction, and use the right-hand rule to determine the direction of current when cutting magnetic field lines.
• Flexibly apply the formulas E = n \frac{\Delta \Phi}{\Delta t} and E = Blv \sin \theta to calculate induced electromotive force in different physical situations.
• Analyze complex electromagnetic phenomena such as self-inductance, eddy currents, and electromagnetic damping from the perspective of energy conversion, and solve relevant real-world physics problems.

🔹 Lesson 3: Alternating Current: Generation Principle, Transformation, and Power Transmission

Overview: This course covers the entire process from the generation of alternating current to its long-distance transmission. Students will first study the physical model of a rectangular coil rotating in a uniform magnetic field to understand the principle of sinusoidal AC generation and its mathematical description (instantaneous value, peak value, and RMS value); then examine the unique opposition effects of inductance and capacitance on AC; finally, explore practical applications by learning the transformation rules of ideal transformers and how high-voltage transmission reduces power loss over long distances.

Learning Outcomes:

• Analyze the process by which a rotating coil generates alternating current, skillfully write expressions for instantaneous values, and convert between peak and root mean square (RMS) values.
• Master the basic principles of ideal transformers, and use the proportional relationship between voltage and number of turns to solve circuit problems.
• Understand the mechanism of power loss in long-distance transmission, calculate voltage drop and power loss in transmission lines, and explain the economic benefits of high-voltage transmission.

🔹 Lesson 4: Electromagnetic Oscillations and Electromagnetic Waves: Maxwell’s Theory and Material Properties

Overview: This lesson aims to help students understand the transition of electromagnetic phenomena from macroscopic circuits to spatial propagation. It begins by exploring the process of electromagnetic oscillation in LC circuits and their energy transformation patterns, then delves into the two core assumptions of Maxwell’s electromagnetic field theory, ultimately revealing the principles of electromagnetic wave emission and reception, their material properties, and their broad spectrum.

Learning Outcomes:

• Describe the periodic changes in charge, current, electric field energy, and magnetic field energy within an LC oscillating circuit.
• Master the formulas for the period and frequency of electromagnetic oscillations, and perform related quantitative calculations.
• Understand the core content of Maxwell’s electromagnetic field theory, explain the material nature of electromagnetic waves, and identify components of the electromagnetic spectrum.

🔹 Lesson 5: Sensors: Core Components, Operating Principles, and Circuit Design

Overview: This lesson aims to deepen students’ understanding of sensors through comprehensive exploration of their definition, composition, and application modes. Students will learn the working principles of key sensitive elements such as photoresistors, thermistors, and magnetoresistive (Hall effect) elements. By analyzing capacitive and inductive displacement sensors, as well as the temperature control system in rice cookers, students will understand how non-electrical quantities are converted into electrical signals. Finally, through designing circuits for burglar alarms and light-controlled switches, students will develop engineering thinking to solve real-world problems.

Learning Outcomes:

• Accurately describe the definition, structural composition (sensitive elements and transducer elements), and general application models of sensors.
• Understand the physical mechanisms by which photoresistors, thermistors, Hall elements, and capacitive/inductive sensors convert physical quantities into electrical signals.
• Analyze the temperature control principle of rice cookers, and design simple automatic control circuits (such as burglar alarms and light-controlled switches) based on experimental needs.