Video: Watch this Demo
Description: This demo shows how temperature affects the magnetic properties of a ball of iron.
- Metal pot
- Iron ball
- Bar magnet
- Metal stand with clamps
- Assemble the ring stand and clamp as shown in the above pictures
- Attach the bar magnet to the clamp and position the metal pot directly below it on the bench
- Attach the iron ball to the magnet above the pot
- Begin heating the iron ball with the torch
- After the ball has fallen turn off the torch and be careful not to touch the heated iron ball or magnet
Explanation: Ordinarily, a ball of iron will be attracted to a magnet but when you heat the ball to a temperature of at least 176° F (the Curie point), it loses its ability to be magnetized. The increasing energy makes the magnetic domains in the iron less stable meaning they are unable to align and create a magnetic field.
Note: Be cautious when using the blowtorch, and be careful not to directly heat the magnet.