Answer:
For a closed organ pipe, the point at the closed end is always a node, 'N' while the open end is always an antinode, 'A'
Therefore, for a closed organ pipe, we only have;
NA = N↔A = First harmonics = f₁
NANA = NA↔AN↔ NA = Third harmonics, = f₃ = 3·f₁
NANANA = NA↔AN ↔ NA ↔ AN ↔ NA = f₅ = 5·f₁
It can also be shown that for a closed organ pipe, only f₇, f₉, f₁₁, ... are present
Therefore, a closed organ pipe has only odd harmonics present
For an open organ pipe, we have;
ANA = First harmonics = f₁
ANANA = ANA ↔ ANA = Second harmonics = f₂ = 2·f₁
ANANANA = ANA ↔ ANA ↔ ANA = Third harmonics = f₃ = 3·f₁
Similar relationship exist for f₄, f₅, f₆...
Therefore, for an open organ pipe, all harmonics, (multiples of the fundamental, f₁) are present
Step-by-step explanation: