Lenz's Law Demonstration

Watch how a falling magnet slows down dramatically when passing through a copper tube due to induced eddy currents that oppose the motion.

Controls

Magnet Strength Medium

Tube Material Copper

Tube Length Medium

Free Fall Time

~0.45s

Through Tube

0.00s

Live Data

Magnet Position

Top

Fall Speed

0 m/s

Drag Force

None

Time in Tube

0.00s

Current Status

No current induced

Experiment Setup

• Magnet is dropped through a conductive tube

• Changing magnetic field induces eddy currents

• Currents create opposing magnetic field

• Magnet falls slowly due to magnetic drag

Eddy Current Status

No current induced

Lenz's Law Explained

When a magnet falls through a conductive tube, its motion creates a changing magnetic field inside the tube. According to Faraday's Law, this changing magnetic field induces electric currents (eddy currents) in the conductor.

Lenz's Law:

"The direction of the induced current is such that it opposes the change that produced it."

The induced eddy currents create their own magnetic field that opposes the magnet's motion. This magnetic drag force slows down the magnet's fall dramatically compared to free fall through air or a non-conductive tube.

Key factors affecting the drag force:

Conductivity: Better conductors (copper, aluminum) create stronger eddy currents
Magnet strength: Stronger magnets induce stronger currents
Tube thickness: Thicker conductive material allows more current flow