The World of Colours and Vision — Important Questions

Red, Green, Blue

The primary colors of light are Red, Green, and Blue (RGB). These three colors can be combined in different proportions to produce all other colors including white light. Yellow, Magenta, and Cyan are secondary colors formed by combining two primary colors: Yellow = Red + Green, Magenta = Red + Blue, Cyan = Green + Blue.

Refraction, Dispersion, Internal reflection

Rainbow formation involves three optical phenomena: 1) Refraction - when sunlight enters and exits water droplets, 2) Dispersion - white light splits into component colors due to different wavelengths, 3) Internal reflection - light reflects inside the droplet before exiting. These three phenomena work together to create the beautiful arc of colors we see.

Dark/No light

A blue filter only transmits blue light and blocks all other colors. When red light falls on a blue filter, the red light is absorbed and no light passes through. Therefore, the result is darkness or no light transmission. This demonstrates the principle that colored filters only allow their own color to pass through.

UV rays, Visible light, IR rays

In the electromagnetic spectrum, wavelength increases in the order: Ultraviolet rays (shortest wavelength), Visible light (medium wavelength), Infrared rays (longest wavelength). UV rays have higher frequency and shorter wavelength, while IR rays have lower frequency and longer wavelength compared to visible light.