What is acoustic length in a pipe or tube?

[polaris90]

What is acoustic length in a pipe/tube? On a physics lab, the lab write up mentions it but it doesn't explain what it is. I know it's give by L = λ/4 and higher ones will be odd multiples of the first one. But what does this actually mean and what is it for? I looked it up but couldn't find any information.
Some help would be appreciated.

 

[tiny-tim]

hi! polaris90!

acoustic length of a tube is an imaginary measurement that's longer than the actual length …

you put it into equations (instead of the actual length), and the equations work!

see eg http://www.flutopedia.com/acoustic_length.htm for details, and lots of pretty pictures​

 

[polaris90]

ok, thank you. That was very helpful