The period of a wave is found to be 50 seconds. What is the frequency of the wave?

If you remember this one rule, then you can always convert

in either direction between frequency and period.

(Frequency) times (Period) = 1.

So Frequency = 1 / period

= 1 / (50 seconds)

= (1/50) per second

= 0.02 per second

= 0.02 Hertz

The answer is this.

1/50 = 0.02 Hz