Why does the sky appear blue during the day?

Question

Accepted Answer

## Model Answer The sky appears blue due to **scattering of light** by fine particles (molecules of air and fine dust) in the atmosphere. These particles are smaller than the wavelength of visible light and scatter shorter wavelengths (blue light) much more strongly than longer wavelengths (red light). The scattered blue light enters our eyes, making the sky appear blue. *Source: Chapter 10, Section 10.6.2 – Why is the colour of the clear Sky Blue?* --- ## Explanation - **Two key points** the examiner expects: (1) scattering of sunlight by fine atmospheric particles, and (2) blue light (shorter wavelength) is scattered more than red light (longer wavelength). - Mention that scattered blue light reaches our eyes — this completes the explanation. - Avoid vague statements like "light bends" — use the correct term **scattering**. - A bonus fact (not required but useful): if there were no atmosphere, the sky would appear dark — shows depth of understanding.

Science (086) — AI-generated practice question