Eddy Current Demonstrator – Lenz’s Law & Magnetic Braking Physics Apparatus

The Eddy Current Demonstrator provides a clear, hands-on way to explore Lenz’s Law and electromagnetic induction in the classroom. This simple yet powerful device uses a copper tube and two visually identical slugs—one plain steel, the other a strong neodymium magnet—to show how eddy currents create magnetic braking forces.

When the steel slug is dropped through the 12-inch copper tube, it falls quickly. In contrast, the magnet descends slowly, visibly slowed by eddy currents induced in the copper walls. This striking difference offers a memorable illustration of energy conservation, induction, and magnetic resistance in action.

Perfect for physics demonstrations, this apparatus is durable, engaging, and comes with an activity guide to support lesson planning.

Tube Length: 12" copper tube

Slugs: One plain steel, one strong neodymium magnet (both with rubber end caps)

Concepts Demonstrated: Lenz’s Law, electromagnetic induction, magnetic braking, energy transfer

Includes: Activity guide for classroom demonstrations