— Frequency ↔ Wavelength ↔ Period
Converts between frequency, period, and wavelength for a periodic wave using T = 1/f and the wave equation v = fλ. Pick whichever quantity you know and solve for the other two. Propagation velocity defaults to the speed of light in vacuum (c ≈ 2.998×10&sup8; m/s) — override it for sound, or for a transmission line using its velocity factor × c.