Final answer:
Combining red, green, and blue wavelengths produces white light due to additive color mixing because these colors contain all the wavelengths needed to be perceived as white by our visual system.
Step-by-step explanation:
When lights of red, green, and blue wavelengths are combined, they produce a colorless or white light. This is known as additive color mixing and it occurs because the three colors contain all the wavelengths necessary to stimulate our visual system in a way that is perceived as white. In the RGB color model used for systems such as television screens and computer monitors, red, green, and blue lights are mixed in various proportions to create a full spectrum of colors, including white. The specific wavelengths in nanometers for red light are approximately 650-700 nm, for green light approximately 495-570 nm, and for blue light approximately 450-495 nm.