Overview
This lecture explains the differences between transverse and longitudinal waves, including how particles move in each type and common examples.
Wave Basics
- Waves transfer energy from one place to another without transferring matter.
- Waves are described by frequency, wavelength, and amplitude.
Longitudinal Waves
- In longitudinal waves, particles vibrate parallel to the direction of wave energy travel.
- Compressions are areas where particles are bunched together; rarefactions are where they are furthest apart.
- Sound waves are an example of longitudinal waves.
- In sound, vibrations pass from particle to particle until reaching the ear.
- Only energy travels; particles stay in roughly the same place.
Transverse Waves
- In transverse waves, particles vibrate at 90 degrees (perpendicular) to wave energy movement.
- The hand moves up and down, but the energy moves horizontally along the slinky.
- Water surface waves and all electromagnetic waves (e.g., visible light) are transverse waves.
- Wavelength and amplitude are commonly shown and measured in transverse waves.
Key Terms & Definitions
- Wavelength — the distance between two corresponding points on a wave (e.g., crest to crest).
- Amplitude — the maximum displacement of particles from their rest position.
- Frequency — the number of complete waves passing a point per second.
- Longitudinal wave — a wave where particle vibration is parallel to energy direction.
- Transverse wave — a wave where particle vibration is perpendicular to energy direction.
- Compression — area in a longitudinal wave where particles are close together.
- Rarefaction — area in a longitudinal wave where particles are far apart.
Action Items / Next Steps
- Practice labeling amplitude and wavelength on wave diagrams.
- Be able to describe and identify examples of both wave types.