How Does Waves and Sound Note 12: Open and Closed Air Columns Work?

A closed air column is like a straw that’s only open at one end, and an open air column is like a straw that's open on both ends, and they each make different kinds of sounds when you blow into them.

Imagine blowing across the top of a soda bottle. That makes a note. In a closed air column, it’s like you're blowing into one end of a pipe, while the other end is sealed, like a straw with your thumb over one side. This kind of column can only make some notes, specifically, the lowest note and then every second note after that.

On the other hand, an open air column is like blowing across both ends of a pipe, or two straws taped together at the bottom. These kinds of columns can make more notes, the lowest note, and then every note in between.

Think about it like playing with a slinky. If one end is fixed (like a closed column), only some waves can go through, but if both ends are free to move (like an open column), all kinds of waves can bounce around, making more notes!