Final answer:
The period of the water waves passing under the bridge can be calculated using the formula T = 1 / f, where f is the frequency. In this case, the frequency is approximately 0.2381 Hz.
Step-by-step explanation:
The period of a wave is the time it takes for one complete wave cycle to pass a given point. In this case, the water waves passing under the bridge have a rate of one complete wave every 4.2 seconds.
To find the period, we can use the formula:
Period (T) = 1 / Frequency (f)
In this case, since the frequency is not given directly, we can calculate it by taking the reciprocal of the period:
Frequency (f) = 1 / 4.2 s
Plugging in the values, we get:
f = 0.2381 Hz
Therefore, the frequency of these waves is approximately 0.2381 Hz.