| English | Faraday's law of electromagnetic induction |
|---|---|
| Bahasa Melayu | Hukum aruhan elektromagnet Faraday |
| 中文 | 法拉第电磁感应定律 |
Definition
The magnitude of the induced electromotive force is directly proportional to the rate of change of magnetic flux linking the conductor.
In exam terms
Faraday's law of electromagnetic induction states that the magnitude of the induced electromotive force (e.m.f.) is directly proportional to the rate of change of magnetic flux linking the conductor. The induced e.m.f. is measured in volts (V).
In practice this means the induced e.m.f. is larger when the magnet moves faster, the magnetic field is stronger, or the coil has more turns, because each raises the rate of change of flux linkage. Example of correct use: Doubling the speed at which the magnet is pushed into the coil doubles the induced e.m.f. Faraday's law gives the size of the e.m.f.; Lenz's law gives its direction.
Do not confuse it with…
Do not confuse Faraday's law with Lenz's law. Faraday's law tells you the size of the induced e.m.f.
(proportional to the rate of change of flux), while Lenz's law tells you its direction (it opposes the change causing it). They answer different parts of the same problem.
In Paper 2 this is asked as state or explain: state Faraday's law, or explain how the induced e.m.f. changes when a factor is altered. When answering, always refer to the rate of change of magnetic flux, not just the flux itself.
Source: DSKP KSSM Physics Form 4 and 5 (Versi English) (Bahagian Pembangunan Kurikulum (BPK), KPM)