The lower the frequency the ______ the wavelength.

The lower the frequency the ______ the wavelength.

• A. Shorter
• B. Longer
• C. Same
• D. Inverse

Answer: (B)

Wavelength and frequency are tied through the wave’s speed: speed equals frequency times wavelength. In a given medium, that speed is fixed, so lowering the frequency must push the wavelength higher to keep the product the same. For light in vacuum, λ = c/f, so as f decreases, λ increases. That makes the correct completion “Longer.” The other options don’t fit: shorter would require a higher frequency, same would imply no change in wavelength, and while the relationship is inversely proportional, that word isn’t the natural completion for this sentence.

Wavelength and frequency are tied through the wave’s speed: speed equals frequency times wavelength. In a given medium, that speed is fixed, so lowering the frequency must push the wavelength higher to keep the product the same. For light in vacuum, λ = c/f, so as f decreases, λ increases. That makes the correct completion “Longer.” The other options don’t fit: shorter would require a higher frequency, same would imply no change in wavelength, and while the relationship is inversely proportional, that word isn’t the natural completion for this sentence.