In wave diffraction, which two factors primarily determine how much a wave spreads after passing through an opening (or around an obstacle)?

• A. The medium’s density and the wave’s phase at the opening
• B. The wave’s amplitude and the distance the wave travels after the opening
• C. The wavelength of the wave and the size (width) of the opening/obstacle relative to that wavelength
• D. The wave’s frequency and its polarization direction

Answer: (C)

Verified step by step guidance

1. Understand that wave diffraction refers to the bending and spreading of waves when they encounter an obstacle or pass through an opening.
2. Recognize that the amount of diffraction depends on the relationship between the wavelength of the wave and the size of the opening or obstacle.
3. Recall the principle that when the size of the opening is comparable to or smaller than the wavelength, significant diffraction (spreading) occurs.
4. Note that if the opening is much larger than the wavelength, the wave will spread less and behave more like a straight beam.
5. Conclude that the two primary factors determining the extent of diffraction are the wavelength of the wave and the size (width) of the opening or obstacle relative to that wavelength.