English: The fundamental frequency of a sound wave in a tube with left end CLOSED can be found using the following equation:

${\displaystyle f_{0}={\frac {v}{4L}}}$

L can be found using the following equation:

${\displaystyle L={\frac {\lambda }{4}}}$

λ (lambda) can be found using the following equation:

${\displaystyle \lambda ={\frac {v}{f_{0}}}}$