Frequency and beam divergence are ______ related.

Frequency and beam divergence are ______ related.

• A. Inversely
• B. Directly
• C. Not related
• D. Proportionally

Answer: (A)

Beam divergence is governed by diffraction: for a fixed aperture, the spread of the beam grows with the wavelength. Since wavelength and frequency are tied by λ = c/f, the divergence scales with λ and thus scales inversely with frequency. In other words, higher frequency (shorter wavelength) produces a narrower beam, while lower frequency (longer wavelength) broadens it. This makes the relationship inverse: frequency up, divergence down; frequency down, divergence up. The other ideas—directly related or not related—don’t fit because diffraction links how wide a beam spreads directly to the wavelength, which moves opposite to frequency.

Beam divergence is governed by diffraction: for a fixed aperture, the spread of the beam grows with the wavelength. Since wavelength and frequency are tied by λ = c/f, the divergence scales with λ and thus scales inversely with frequency. In other words, higher frequency (shorter wavelength) produces a narrower beam, while lower frequency (longer wavelength) broadens it. This makes the relationship inverse: frequency up, divergence down; frequency down, divergence up. The other ideas—directly related or not related—don’t fit because diffraction links how wide a beam spreads directly to the wavelength, which moves opposite to frequency.