Sorry. Suspension bridges are only parabolic if their weight is zero! Not very likely in the real world. Their real shape would be a Catenary curve first described about 1690.

Of course, Music is heavily based on maths, for example the relationships between semitones in the even-tempered scale is based on the 12th root of 2.

A perfect 5th has a frequency ratio of 3:2,i.e. 1.5, but an even tempered 5th is VERY slightly flatter, being the (12th root of 2) to the power of 7. Easy to work out on your calculator.