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by defaultcompany 451 days ago

  // Beware the SI's broken definition
  // of Hz.  You should treat the radian as being correct, as a fundamental
  // dimensionless property of the universe that falls out of pure math like
  // the Taylor series for sin[x], and you should treat the Hz as being a 
  // fundamental property of incompetence by committee.
This is all quite entertaining.
1 comments

This is gold.

> In other words, if you use the Hz in the way it's currently defined by the SI, as equivalent to 1 radian/s, you can point to the SI definitions and prove that you follow their definitions precisely. And your physics teacher will still fail you and your clients will think you're completely incompetent because 1 Hz = 2 pi radians/s. And it has for centuries. You are both simultaneously both right and both wrong. You cannot win. You are perfectly right. You are perfectly wrong. You look dumb and unreasonable. The person arguing the opposite looks dumb and unreasonable.

Huh? Seems this quote confuses correspondence and equivalence. A frequency f = 1 Hz = 1 s^-1 (aka cycle/s != rad/s) corresponds to an angular frequency ω = 2π rad/s (ω = 2π f) but they're distinct concepts and quantities. The Hz was introduced in SI with all those considered. Basically both statements "1 Hz = 1 rad/s" and "1 Hz = 2π rad/s" are wrong. The only dumb is this quote tbh.
The point being made in that file is really that, if you take the SI definitions literally, 'cycles' and 'radians' end up both being dimensionless and equal to 1, which is stupid.