http://www.bbc.co.uk/schools/gcsebitesize/science/aqa/waves/generalwavesrev1.shtml
Source: http://www.bbc.co.uk/schools/gcsebitesize/science/aqa/waves/generalwavesrev1.shtml
A brief introduction to waves for P1 5 (Science A/Physics)
Source: Mrs G Boyson: http://www.knowmia.com/watch/lesson/45483