Electromagnetism 2 min
How Eddy Current Brakes Work (Stopping a Train Without Touching It)
A magnet near a spinning copper disc slows it down without touching it. The moving metal sees a changing field, currents swirl inside it, and those currents push back. That is an eddy current brake: no contact, no wear, and a braking force that grows with speed.
The video shows the induced loops, the force direction from Lenz's law, and where this is used, from roller coasters to trains.
In this video
- How a moving conductor induces eddy currents
- Why the force opposes the motion
- Why braking force grows with speed and vanishes at rest
- Roller coasters, trains and the drop-tube demo