# Frostbite Theater

Here's a Question! - Which Melts First?

Two, essentially identical ice cubes, are placed in liquid nitrogen. One ice cube is left in the liquid nitrogen for one hour. The other ice cube is left in the liquid nitrogen for five hours. Both ice cubes are removed from the liquid nitrogen and are allowed to melt under essentially identical conditions. Which ice cube melts first?

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: Two, essentially identical ice cubes, are placed in liquid nitrogen.

Joanna: One ice cube is left in the liquid nitrogen for one hour.

Steve: The other ice cube is left in the liquid nitrogen for five hours.

Joanna: Both ice cubes are removed from the liquid nitrogen and are allowed to melt under essentially identical conditions.

Steve: Which ice cube melts first?

Joanna: The one that was in the nitrogen for an hour?

Steve: The one that was in the nitrogen for five hours?

Joanna: Do they both melt at essentially the same rate?

Steve: Or, are the ice cubes now invulnerable to melting?

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

Joanna: One hour is plenty of time for an ice cube to reach thermal equilibrium with liquid nitrogen, let alone five, so both ice cubes are the same temperature when they're removed from the liquid nitrogen.

Steve: But, the ice cube that was in the nitrogen for five hours isn't 'more cold' just because it's been cold for longer. It's like if you have \$10 in your pocket. If you have \$10 in your pocket, then you have \$10 in your pocket. It doesn't matter how long the \$10 has been there.

Joanna: Since both ice cubes are essentially identical and are melting under essentially identical conditions and start at the same initial temperature, both ice cubes melt at essentially the same rate.

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

Joanna and Steve: Essentially.