IB›IB Physics SL›Mind mapsC.2 Wave modelIB Physics SL: Mind mapStudy pack PDFAlso for this subtopic:Revision notesFlashcardsSubtopic testCover factsWave typesWaves transfer energy, not matterTransverse: oscillation perpendicular to energy transferLongitudinal: oscillation parallel, compressions and rarefactionsSound and P-waves are longitudinalDescribing wavesWavelength: distance between adjacent in-phase pointsT=1fT = \frac{1}{f}T=f1v=fλ=λTv = f\lambda = \frac{\lambda}{T}v=fλ=TλMedium sets speed, source sets frequencySoundLongitudinal mechanical waveCannot travel through a vacuumAbout 340 m s⁻¹ in air, 1500 in waterAbout 5000 m s⁻¹ in steelHuman hearing: 20 Hz to 20 kHzWave modeltravelling wavesλ\lambdaλfffTTTvvvEM wavesTransverse oscillating electric and magnetic fieldsNeed no mediumc=3.00×108 m/sc = 3.00 \times 10^8\,\text{m/s}c=3.00×108m/s in vacuumRadio → microwave → infrared → visible → UV → X-ray → gammaMechanical versus EMMechanical waves need a medium, EM do notMechanical: transverse or longitudinal; EM: transverse onlyBoth show reflection, refraction, diffractionExam tipsHigher f in same medium gives shorter λ, not higher vComparisons: state both sides of each difference