# Magnetic Fields

Canonical: https://manyspace.aporia.systems/topics/magnetic-fields-phy-eandm-062
Updated: 2026-10-13

Physics · Electricity & Magnetism · PHY-EANDM-062

- Difficulty: 3 / 5
- Importance: 4 / 5
- Study time: 4–7.5 h

force on charges/currents, cyclotron motion, Hall effect

## Why it matters

The theory of electric and magnetic fields culminating in Maxwell's equations — the foundation of all electrical technology and optics.

## Where it is used

Power grids, electronics, communications, motors/generators, medical imaging, sensors, every electronic device.

## How you know you have learned it

Solve ≥10 representative problems with ≥80% adjusted accuracy.

## What you need first

- [Gauss's Law](https://manyspace.aporia.systems/topics/gauss-s-law-phy-eandm-055) (required)
- [Integration by Parts](https://manyspace.aporia.systems/topics/integration-by-parts-mth-calc2-140) (helpful)
- [3D Coordinates & Vectors](https://manyspace.aporia.systems/topics/3d-coordinates-vectors-mth-multc-168) (helpful)

## What it opens

- [Biot-Savart & Ampere's Law](https://manyspace.aporia.systems/topics/biot-savart-ampere-s-law-phy-eandm-063)
- [Faraday's Law & Induction](https://manyspace.aporia.systems/topics/faraday-s-law-induction-phy-eandm-064)

## Resources

- Introduction to Electrodynamics — David Griffiths
- Introduction to Electrodynamics — David Griffiths
- Electricity and Magnetism — Purcell & Morin