Which color of visible light has the longest wavelength, and which has the shortest wavelength?

• A. Violet has the longest wavelength; red has the shortest wavelength.
• B. Yellow has the longest wavelength; orange has the shortest wavelength.
• C. Blue has the longest wavelength; green has the shortest wavelength.
• D. Red has the longest wavelength; violet has the shortest wavelength.

Answer: (D)

Verified step by step guidance

1. Recall that visible light is a portion of the electromagnetic spectrum with wavelengths approximately between 400 nm and 700 nm.
2. Understand that the color of visible light corresponds to a specific range of wavelengths: red light has the longest wavelength, and violet light has the shortest wavelength within the visible spectrum.
3. Remember the order of colors in visible light from longest to shortest wavelength: Red, Orange, Yellow, Green, Blue, Indigo, Violet (often remembered by the acronym ROYGBIV).
4. Identify that red light has wavelengths around 620-750 nm, making it the longest wavelength visible to the human eye.
5. Identify that violet light has wavelengths around 380-450 nm, making it the shortest wavelength visible to the human eye.