Article 2nd paragraph: "Suppose a string of a certain tension and length produces an A when plucked. If you make the string twice as tight, or keep the same tension and cut the string in half, the string will sound the A an octave higher."
This is not even dimensionally correct. The frequency is proportional to the square root of the tension.
Later: "The ratio of 3/2 is called a “perfect” fifth to distinguish it from the ratio 1.498."
I don't think so. The interval is called a "perfect" fifth to distinguish it from the "diminished" or "augmented" fifth. Nothing to do with tuning.
This is not even dimensionally correct. The frequency is proportional to the square root of the tension.
Later: "The ratio of 3/2 is called a “perfect” fifth to distinguish it from the ratio 1.498."
I don't think so. The interval is called a "perfect" fifth to distinguish it from the "diminished" or "augmented" fifth. Nothing to do with tuning.