7.2.2—Graphical representations of transverse and longitudinal waves
- Syllabus
- 9702–2028–2029
- Objective
- 7.2.2
- Level
- AS
Wave diagrams use displacement, position and time axes to show phase and wavelength
A displacement–distance graph shows the shape at one instant and a displacement–time graph shows one point’s oscillation; wavelength and period must be read from the correct axis.
Measure crest-to-crest or equivalent phase spacing for λ, and cycle time for T. Do not mix a spatial graph with a time graph.
A displacement–distance graph with 0.80 m between adjacent crests has λ=0.80 m; a time graph with 0.20 s per cycle has f=5 Hz.
Amplitude is read vertically on both graphs, but horizontal scale represents distance in one and time in the other.
ConceptA-Level CAIE Physics AS