Electromagnetic Induction: Key Revision Notes for WJEC A-Level Physics | 电磁感应考点精讲

📚 Electromagnetic Induction: Key Revision Notes for WJEC A-Level Physics | 电磁感应考点精讲

Electromagnetic induction is one of the most fundamental concepts in A-Level Physics and a regular feature in WJEC examinations. It describes the generation of an electromotive force (emf) across a conductor when it experiences a changing magnetic field. Mastery of Faraday’s law, Lenz’s law, and their applications in generators, transformers, and eddy currents is essential for top marks. This article provides a comprehensive breakdown of the topic with bilingual explanations, key formulas, and exam tips.

电磁感应是 A-Level 物理中最基础的概念之一，在 WJEC 考试中频繁出现。它描述了当导体处于变化的磁场中时，导体两端产生电动势的现象。掌握法拉第定律、楞次定律及其在发电机、变压器和涡流中的应用是取得高分的必备条件。本文通过双语讲解、关键公式和备考提示，为你全面梳理该考点。

1. Introduction to Electromagnetic Induction | 电磁感应导论

Electromagnetic induction occurs whenever there is a change in the magnetic flux linking a circuit. The phenomenon was discovered by Michael Faraday and forms the backbone of modern electrical power generation. In WJEC Physics, you need to state the conditions for induction, apply Faraday’s law quantitatively, and use Lenz’s law to predict the direction of induced currents.

电磁感应发生在回路所交链的磁通量发生变化时。该现象由法拉第发现，是现代电力生产的基石。在 WJEC 物理考试中，你需要说明感应产生的条件，定量应用法拉第定律，并运用楞次定律判断感应电流的方向。

Common demonstrations include moving a bar magnet into a coil, switching a current on or off in a neighbouring coil, and rotating a coil in a uniform magnetic field. In

Published by TutorHao | A-Level Physics Revision Series | aleveler.com

更多咨询请联系16621398022（同微信）