Lecture on Transverse and Longitudinal Waves

Objectives

• Describe differences between transverse and longitudinal waves.
• State examples of these types of waves.
• Understand evidence that waves move but not the medium.

Types of Waves

• Transverse Waves
  • Example: Ripples on the surface of water.
• Longitudinal Waves
  • Example: Sound waves traveling in air.

Key Characteristics of Waves

• All waves fall into one of two categories: Transverse or Longitudinal.
• Waves transfer energy from one place to another:
  • Ripples transfer kinetic energy.
  • Sound waves transfer sound energy.

Transverse Waves

• Description:
  • Movements are oscillations which are perpendicular to the direction of energy transfer.
  • "Perpendicular" means at right angles.
  • Example: Water ripples (oscillate up and down while energy moves sideways).

Longitudinal Waves

• Description:
  • Sound waves travel as particles move side to side.
  • Regions of compression and rarefaction.
  • Oscillations are parallel to the direction of energy transfer.
• Medium Requirement:
  • Require a medium to travel through (air, liquid, or solid).

Important Facts

• In both ripples on water and sound waves in air, the wave itself travels, not the medium.
  • Example using a slinky:
    • Transverse Representation: Red dot oscillates up and down, representing a water molecule.
    • Longitudinal Representation: Red dot oscillates side to side, representing an air particle.

Additional Resources

• Practice questions available in the revision workbook linked above.

These notes capture the essential aspects of the lecture on transverse and longitudinal waves, providing a structured outline for review.