Mains electrical power in some countries alternates at 60.0 Hz. What is the period of that oscillation?

1. Period is the reciprocal of frequency, T = 1 / f. 2. T = 1 / 60.0 Hz = 1.67 x 10^-2 s. 3. Converting, 1.67 x 10^-2 s = 16.7 ms. 4. Quoting 1.67 ms slips one power of ten and would describe a 600 Hz supply. 5. Quoting 60.0 ms reuses the frequency digits as if they were a time. _Source: OpenStax College Physics (CC BY 4.0), Ch 16 "Oscillatory Motion and Waves", section 16.2 Period and Frequency in Oscillations_