The Franklin Institute Traveling Science Show

Hot and Cold

We are a bunch of molecules, just hanging out.

See what happens when we get cold!

We pack in close, tight!

Liquid nitrogen!  Now that's cold!

Do things expand or contract when the temperature changes?

When things get very cold they become brittle - and can shatter into pieces!

Which gas can inflate the balloon faster?

Liquid nitrogen or carbon dioxide?

Flight

The French came up with the idea that hot air rises.  Know how?

They noticed that underpants hung in the fireplace to dry went up the chimney!

Hydrogen is not used in hot air balloons today - it explodes too easily.

Newton's 3rd Law of Motion - for every action there is a reaction.