## Episode 316: Preparation for reflection and refraction topic

Teaching Guidance for 16-19

- Level Advanced

The demonstration of refraction using a ripple tank is tricky, and it is a good idea to practise this.

#### Main aims of this topic

Students will:

- know how to justify the law of reflection by a wave diagram
- know how to justify Snell’s law in terms of wave velocities
- be able to perform calculations involving the refractive index
- be able to perform calculations involving critical angle
- know the benefits of fibre optic communication

#### Prior knowledge

Students should know:

- the law of reflection
- the law of refraction, or at least have a qualitative knowledge of refraction

#### Where this leads

This work explains the behaviour of light in terms of waves; this is particularly important as diffraction and interference follow (as the result of superposition of waves).