How sound travels
How sound travels

Sound is a longitudinal mechanical wave produced by a vibrating source. The source pushes and pulls nearby particles, creating alternating compressions and rarefactions that transfer energy through a medium.
Step-by-step lessons on Edexcel GCSE Physics 4.3 Sound, ultrasound and infrasound (physics only). Each one builds up to exam-style questions. Master the required practical work and core equations early, since both papers can draw on content and maths skills from across the whole specification.