The velocity of the wave (v) can be calculated using the formula:
v = distance / time
where distance is 100 m and time is 5 s, so:
v = 100 / 5 = 20 m/s
The frequency of the wave (f) is related to its velocity and wavelength (λ) by the formula:
v = f x λ
where λ is the distance between successive crests of the wave, which is 25 cm or 0.25 m.
Rearranging the formula, we get:
f = v / λ
Plugging in the values, we get:
f = 20 / 0.25 = 80 Hz
Therefore, the frequency of the wave is 80 Hz.