The period of a wave is the time it takes for one complete cycle. It's the inverse of the frequency. Here's how to calculate it:

* Frequency (f): 1000 Hz (Hertz)

* Period (T): 1 / f

Therefore:

* T = 1 / 1000 Hz = 0.001 seconds

So, the period of a wave with a frequency of 1000 Hz is 0.001 seconds (or 1 millisecond).