9702 · 20.5
Electromagnetic induction
Ever wondered how electricity is generated in power plants? It's largely thanks to **electromagnetic induction**! This fundamental principle describes how a changing magnetic field can create an electric current. We'll explore the concepts of **magnetic flux**, **Faraday's Law**, **Lenz's Law**, and the fascinating **Hall Effect**, all crucial for understanding how generators and sensors work. This pilot aligns with **Senpai Corner** A Level notes (2025–2027) for topic **20.5**.
Need to know
What you need to know
- $\Phi$ is the magnetic flux (in Webers, Wb).
- B is the magnetic flux density (in Tesla, T).
- A is the area through which the field lines pass (in m²).
- $\theta$ is the angle between the magnetic field B and the normal to the area A.
- Maximum flux occurs when the field is perpendicular to the area ($\theta = 0^\circ$, $\cos 0^\circ = 1$), so $\Phi = BA$.
- Zero flux occurs when the field is parallel to the area ($\theta = 90^\circ$, $\cos 90^\circ = 0$).
Explanation
Electromagnetic induction
- $\Phi$ is the magnetic flux (in Webers, Wb).
- B is the magnetic flux density (in Tesla, T).
- A is the area through which the field lines pass (in m²).
- $\theta$ is the angle between the magnetic field B and the normal to the area A.