http://www.bbc.co.uk/schools/gcsebitesize/science/aqa/waves/generalwavesrev5.shtml
Source: http://www.bbc.co.uk/schools/gcsebitesize/science/aqa/waves/generalwavesrev5.shtml
A brief introduction to diffraction
Source: Mrs G Boyson: http://www.knowmia.com/watch/lesson/45684
A short GCSE revision video for AQA core science and AQA P1 to explain how diffraction works with sound, water and radio waves.
Source: https://youtu.be/-QYQDJ7CSVQ