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LESSON 06

Closed Pipe

Standing waves in pipes closed at one end.

Frequency1.00×
Amplitude1.00×

A closed pipe (like a clarinet) has a node at the closed end and an antinode at the open end. Only odd harmonics are possible.

Boundary conditions

Closed end → displacement node. Open end → antinode.

Harmonics

Frequencies: f_n = n·v / (4L), with n = 1, 3, 5, …

Key Formulas

Odd harmonics
fₙ = n·v / (4L)
n odd
Fundamental
f₁ = v / (4L)
low + warm

Real-life applications

  • Clarinets
  • Test-tube whistles
  • Bottle music

Summary

  • Closed pipe: only odd harmonics.
  • Fundamental is one octave lower than an open pipe of the same length.

Check Yourself

Q1.A clarinet behaves like a…