# A diamond gemstone is well known for its ability to bend light by a large amount compared with other transparent materials. Explain why light bends when it enters a diamond from air at an angle to the normal, and describe how the amount of bending in diamond compares with that in glass.

> Eduqas A-Level Physics — 2.6 Refraction of light · Explain · 5 marks

> Diamonds are cut with many flat faces to make light change direction dramatically as it passes through the stone. This bending of light at a boundary is called refraction.

## Mark scheme (5 marks)

1. Light travels at different speeds in different media / light slows down when it enters diamond from air
2. Because light changes speed, it changes direction / this change in speed causes the light to bend
3. The ray bends towards the normal when entering the diamond from air
4. Diamond slows light down more than glass does / the speed of light in diamond is lower than in glass
5. Therefore light bends more (has a greater change in direction / smaller angle of refraction) in diamond than in glass for the same angle of incidence

## Key terms

- [normal](https://www.gradenine.co.uk/glossary/normal)

## Related

- [Revision notes for Eduqas A-Level Physics](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)

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Source: [GradeNine](https://www.gradenine.co.uk/q/a-diamond-gemstone-is-well-known-73e70e7d) · Published by Druglandscape Ltd.