The distance between two consecutive wave crests is called what?

• A. Wavelength
• B. Amplitude
• C. Frequency
• D. Phase

Answer: (A)

Wavelength is the distance between consecutive wave crests (or troughs) in a wave. It’s the spatial length of one complete cycle of the wave, which helps explain how the wave repeats in space. This differs from amplitude, which describes how tall the wave is; from frequency, which counts how many crests pass a fixed point each second; and from phase, which is about the wave’s position within its cycle at a reference point. Wavelength is measured in meters and links to speed and frequency through the relation v = f λ. For light, different wavelengths correspond to different colors; for water waves, the spacing between ripples is the wavelength.