Overview
This lecture explains the differences between transverse and longitudinal waves, provides examples of each, and discusses how waves transfer energy without moving the medium itself.
Types of Waves
- All waves are categorized as either transverse or longitudinal.
- Examples of waves include ripples on water (transverse) and sound waves in air (longitudinal).
- Waves transfer energy from one place to another (e.g., kinetic energy, sound energy).
Transverse Waves
- In transverse waves, oscillations (movements) are perpendicular (at right angles) to the direction of energy transfer.
- Ripples on the surface of water are examples of transverse waves.
- In these waves, particles move up and down while the wave moves sideways.
Longitudinal Waves
- In longitudinal waves, oscillations are parallel to the direction of energy transfer.
- Sound waves in air are examples of longitudinal waves.
- Air particles move side to side, creating compressions (particles close together) and rarefactions (particles spread out).
- All longitudinal waves require a medium (solid, liquid, or gas) to travel through.
Movement of Waves vs. Medium
- In both types of waves, the wave travels but the medium does not; particles only oscillate.
- Demonstrated by a dot moving up and down (transverse) or side to side (longitudinal) without traveling with the wave.
Key Terms & Definitions
- Transverse Wave — wave with oscillations perpendicular to energy transfer direction.
- Longitudinal Wave — wave with oscillations parallel to energy transfer direction.
- Oscillation — repeated movement back and forth (or up and down).
- Medium — material through which a wave travels.
- Compression — region where particles are close together in a longitudinal wave.
- Rarefaction — region where particles are spread apart in a longitudinal wave.
Action Items / Next Steps
- Review questions on transverse and longitudinal waves in the revision workbook.