AS Edexcel Physics: Superposition of waves

Can anyone give me a link with a good summarisation of superposition of waves? None of the edexcel books give a satisfying explanation (in layman terms); (for someone who has never studied this particular topic)..

Thanks

When two waves travelling in opposite directions overlap each other. If they have the same amplitude and frequency (and phase difference I think) it will result in a single wave with a larger amplitude than the original amplitude. If the waves have different amplitude, frequency (and phase difference I think) they will interrupt each other (destructive interference) and cancel each other out. Hope this helps, trying remember what I can from last year

This is very wrong. The waves don´t have to be travelling in opposite direction in order for superposition to take place. That is only necessary for a standing wave to form. Also superposition can occur for two or more waves. For the superposition to produce a fixed pattern the waves must be coherent ( same frequency, wavelength and waveform and a constant phase relationship) and have a similar amplitude at the point of interference. An example of this fixed patterns are formed when two waves which are in phase (i.e 2pi*n phase difference or what is the same: n*lambda path difference) and interfere contructively or two waves in antiphase (i.e. (2*n 1)pi or what is the same: (n 1/2)lambda path difference) which interfere destructively and completely cancel out. Otherwise, if the waves are not coherent, superposition is simply when two or more waves meet at the same point at the same time and overlap giving a net displacement or amplitude equal to the sum of the displacements/amplitudes that would have been produced by the individual waves separately.

This forum was created in the 17th century. Their physics wasn't as advanced as ours.

gotta get things right

They have to be coherent to superposition right?

Can anyone give me a link with a good summarisation of superposition of waves? None of the edexcel books give a satisfying explanation (in layman terms); (for someone who has never studied this particular topic)..

Thanks