Question

The distance between the first and third crest of an ocean wave is 24 meters. what is the wavelength of the ocean wave? A. 6 meters B. 8 meters C. 12 meters D. 24 meters

Answer 1

The answer is C. 12 meters.

The distance between the crests of an ocean is 1 wavelength. Between the first and the second crest, the distance is 1 wavelength while between the first and the third crest the difference is 2 wavelengths.
If 24 meters are 2 wavelengths, how many meters are 1 wavelength:
24m : 2w = x : 1w
⇒$\frac{24m}{2w} = \frac{x}{1w}$
⇒ x = 12 meters.