Light rays reflecting off mirror tutorial (flat) (physics classroom)
Light ray diagram for plane mirror (geogebra)
2 mirrors at various angles (and multiple reflections) (Vascak)
Longitudinal Wave (Surendranath)
Transverse Wave (Surendranath)
Alarm bell in vacuum jar interactive experiment (Olabs)
interactive site that explains heaps about transverse (and some longitudinal) waves
Refraction step by step (Fendt)
Image of fish in water (apparent depth) (FSU)
2-ray diagram for refraction and image location (Geogebra)
Simplistic image of stick under water (Web Physics)
Diffraction 4 pages of notes & animations from Salford Uni
Diffraction around hills (Salford Uni)