Frostbite Theater

Announcer: Frostbite Theater presents... Cold Cuts! No baloney!

Joanna and Steve: Just science!

Joanna: Hi! I'm Joanna!

Steve: And I'm Steve!

Joanna: Here's a question for you...

Steve: A paperclip is straightened out, except for a loop at the end, and is loosely hung from a staple that's been inserted into a block of wood.

Joanna: The free end of the paperclip is placed close to, but not touching, a strong magnet so that it doesn't fall down.

Steve: A candle is placed under the paperclip's free end.

Joanna: The candle is lit and the flame touches the paperclip.

Steve: What happens to the paperclip?

Joanna: Does the paperclip fall down?

Steve: Does the paperclip burn?

Joanna: Does the paperclip melt and the strong magnet attracts the molten droplets?

Steve: Or, does nothing happen?

Joanna: Pause the video now if you'd like to think it over before we show you what happens.

Steve: Although the paperclip is made from iron, which is a magnetic material, it makes a lousy magnet because its atoms aren't aligned.

Joanna: Some are pointed up.

Steve: Some are pointing down.

Joanna: Some are pointed to the left.

Steve: Some are pointed to the right.

Joanna: Since they're all scrambled up, their magnetic fields cancel each other out.

Steve: Now, we can align some of the atoms by getting the paperclip close to the magnet. Once you have more atoms pointing in one direction than another, the fields add up and the paperclip acts like a magnet.

Joanna: And that's great... at room temperature. Heating the paperclip causes the atoms to jiggle about. Jiggle them too much, and they fall out of alignment again. The temperature at which this happens is called the Curie Temperature. For iron, this is about 770 degrees Celcius, which can easily be done with a candle.

Thanks for watching. I hope you'll join us again soon for another question!