4.01 - 4.03 - Wave Properties
4.04 - Polarisation
4.05 - 4.07 - Refraction
4.08 - Total Internal Reflection
4.09 - Optic fibres
4.10 - 4.11 - Phase Difference & Superposition
4.12 - 4.13 - Stationary wave
4.14 - Wave on a string
4.15 - Phase in stationary waves
4.16 - Diffraction
4.17 - 4.18 - Double slit
4.19 - 4.20 - Diffraction grating
4.21 - Single slit