# A student places a glass prism in the path of a ray of white light. The white light enters one face of the prism and a spectrum of colours emerges from the opposite face. Explain why white light produces a spectrum of colours when it passes through a glass prism.

> WJEC A-Level Physics (Wales) — 2.6 Refraction of light · Explain · 5 marks

## Mark scheme (5 marks)

1. White light is made up of a mixture of different colours (frequencies/wavelengths)
2. Each colour (wavelength/frequency) refracts by a different amount when passing from air into glass
3. Violet light refracts the most and red light refracts the least (or correct comparative statement)
4. The different colours slow down by different amounts when entering the glass (different speeds in glass)
5. The colours are separated / spread out, producing a visible spectrum

## Key terms

- [white light](https://www.gradenine.co.uk/glossary/white-light)
- [spectrum](https://www.gradenine.co.uk/glossary/spectrum)

## Related

- [Revision notes for WJEC A-Level Physics (Wales)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

---
Source: [GradeNine](https://www.gradenine.co.uk/q/a-student-places-a-glass-prism-215b1210) · Published by Druglandscape Ltd.