The period of a wave is the time it takes for one complete cycle of the wave. It is related to the frequency by the following equation:

Period (T) = 1 / Frequency (f)

In this case, the frequency (f) is 10Hz. Therefore, the period (T) is:

T = 1 / 10 Hz = 0.1 seconds

So, the period of a 10Hz wave is 0.1 seconds.