How Do Cube Root Numbers Relate to the Fraction 1/8 in Determining Pitch?

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Discussion Overview

The discussion explores the relationship between cube root numbers and the fraction 1/8 in the context of determining pitch, particularly focusing on how changes in volume and dimensions of objects, like spheres and drumheads, affect pitch. The scope includes theoretical and conceptual aspects of sound production related to geometry.

Discussion Character

  • Conceptual clarification
  • Technical explanation
  • Exploratory

Main Points Raised

  • One participant questions the relationship between cube root numbers and the fraction 1/8, noting that a pitch of 2048 per second is produced by a body with a volume between 1/8 of a reference body and the cube root of that body.
  • Another participant states that the pitch depends on the radius of the sphere, explaining that doubling the radius increases the volume by a factor of 8 (2^3).
  • A participant expresses surprise at the simplicity of the relationship, questioning whether this principle applies only to spheres.
  • It is suggested that the relationship also holds for the frequencies of 3D objects, such as drumheads, where pitch changes according to the square of the dimensions (2^2).

Areas of Agreement / Disagreement

Participants express varying levels of understanding regarding the relationship between volume, dimensions, and pitch. While some agree on the mathematical principles involved, there is uncertainty about the applicability of these principles to different shapes beyond spheres.

Contextual Notes

Participants do not fully resolve the relationship between cube root numbers and the fraction 1/8, nor do they clarify the assumptions regarding the shapes of objects discussed.

PH7SICS
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Dose anyone know the relationship of cube root numbers and the fraction of 1/8

"Assuming a body of a size represented by X has a pitch of 1024 per second, then a pitch of 2048 (double 1024) per second will be produced by a body having a volume of some mean between 1/8 of X and the cube root of X"

I understand why a pitch double the original will be produced by a sphere 1/8 the volume because if you double the diameter of a sphere you increase its volume by eightfold.

I don't however understand the relationship between 1/8 and cube root numbers, any ideas?
 
Last edited:
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The pitch depends on the radius of the sphere. Doubling the radius multiplies the volume by
2^3=8.
 
Is it as simple as that...haha lol, I knew 2^3 was 8 but I had assumed I was looking for something more complex, funny when you look for the complex you miss the simple.

Would this only work for spheres then?
 
It would also work for the frequencies of a 3D object. For a drumhead, the pitch would go like 2^2.
 

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