Electromagnetic Waves

  • Waves
    • Transfer energy (not matter)
  • Production of Sound Waves
    • Produced by a vibrating object
  • Medium
    • The material through which a wave can travel
  • Mechanical Waves
    • Travel only through matter, not through vacuum
    • Types of mechanical waves:
    • Sound waves
    • Water waves
    • Seismic waves
  • Wave Movement
    • Longitudinal waves: Energy moves parallel
    • Transverse waves: Energy moves perpendicular
  • Wave Count
    • If hand makes 5 vibrations, 5 waves are created
  • Types of Wave Diagrams
    • Transverse Wave:
    • Label: wavelength, amplitude, crest, trough, rest line
    • Longitudinal Wave:
    • Label: rarefaction, compression
  • Amplitude and Energy Relationship
    • More energy = higher amplitude
  • Wavelength and Frequency Relationship
    • Longer wavelength = greater frequency
  • Comparing Longitudinal Waves
    • Greater energy = More rarefactions
  • Sound Wave Speed
    • Fastest in solids
    • Slowest in gases
    • Influencing factors: Density and temperature
    • More dense = slower sound travel
  • Wave Definitions
    • Absorption: Wave energy absorbed by an object
    • Reflection: Wave bounces off an object
    • Transmission: Wave transfers through an object
    • Diffraction: Waves spread out after passing through a narrow aperture