Multiple choice

The sky appears blue because some of the blue component of sunlight is scattered by

  1. Gas molecules in air

  2. Dust particles in air

  3. Water droplets suspended in air

  4. Soot particles in air

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Rayleigh scattering occurs when sunlight interacts with the gas molecules in Earth's atmosphere, such as nitrogen and oxygen. Because blue light travels in smaller, shorter waves, it gets scattered in all directions much more than other colors, making the sky look blue.