Final answer:
The frequency of the wave is calculated using the formula frequency (f) = 1 / period (T). As the period is 2 seconds, the frequency is 1 / 2 seconds = 0.5 Hz.
Step-by-step explanation:
The student asks about finding the frequency of the wave when given that the time between crests that pass by is two seconds. To find the frequency, we can use the formula frequency (f) = 1 / period (T). We are given that the time taken for successive crests to pass is 2 seconds, which is the period of the wave. Therefore, the frequency of the wave is 1 / 2 seconds = 0.5 Hz. So, the correct answer from the provided options is D) 0.5 Hz.