Question

A closed organ pipe (closed at one end) is excited to support the third overtone. It is found that air in the pipe has ______.

Options

• three nodes and three antinodes

• three nodes and four antinodes

• four nodes and three antinodes

• four nodes and four antinodes

Answer 1

A closed organ pipe (closed at one end) is excited to support the third overtone. It is found that air in the pipe has four nodes and four antinodes.

Explanation:

The third overtone has a frequency 7n, which means `L = (7λ)/4` = three full loops + one half loop, which would make four nodes and four antinodes.