Ultraviolet light has shorter wavelengths.

• A. Longer wavelengths
• B. The same wavelengths as visible
• C. In the radio frequency range
• D. Shorter wavelengths

Answer: (D)

Wavelength is tied to energy and color: as frequency increases, wavelength decreases. Ultraviolet light sits just beyond the violet end of the visible spectrum, so its photons have a higher frequency than visible light. Since wavelength and frequency are inversely related, ultraviolet light must have shorter wavelengths than visible light. That’s why it’s described as having shorter wavelengths.

Longer wavelengths would place it in the infrared or radio ranges, not ultraviolet. The same wavelengths as visible would imply UV and visible light share the same region, which isn’t true because UV lies beyond the violet boundary. Being in the radio frequency range would mean wavelengths are much longer, which also doesn’t apply to ultraviolet.