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• Types of Waves:

  • Transverse Waves: Vibrate perpendicular to the direction of travel
  • Longitudinal Waves: Vibrate parallel to the direction of travel
• Wave Characteristics:

  • Transverse Waves move up and down (e.g., water waves)
  • Wavelength: Distance between peaks
  • Amplitude: Distance from the center to the top of a wave
  • Longitudinal Waves move back and forth (e.g., slinky spring)
  • Compression: Areas where waves are close together
  • Rarefaction: Areas where waves are spread apart
• Wave Properties:

  • Both transfer energy but not matter
  • Time period: Time for one complete oscillation (measured in seconds)
  • Frequency: Number of vibrations per second (measured in hertz, Hz)
• Wave Equations:

  • Frequency and time period have a reciprocal relationship
  • Wave speed is related to frequency and wavelength
• Diffraction:

  • Waves spread out slightly when passing through a gap
  • Maximum diffraction occurs when the wavelength is approximately equal to the width of the gap
• Electromagnetic Waves:

  • Oscillations of electric and magnetic fields
  • Range from long wave radio to short wave gamma rays
  • All travel at the speed of light
• Electromagnetic Spectrum:

  • Gamma rays → X-rays → Ultraviolet → Visible light → Infrared → Microwaves → Radio waves
  • Higher frequency = more dangerous (e.g., ionizing gamma rays)
• Uses and Dangers of Electromagnetic Waves:

  • Various uses from broadcasting to cooking
  • Microwaves, infrared, ultraviolet, X-rays, and gamma rays have both uses and dangers
• Reflection:

  • Angle of incidence = Angle of reflection
  • Normal line: Drawn at 90 degrees to the surface
  • Image formed inside the mirror is laterally inverted
• Refraction:

  • Wave changes speed and direction when passing from one medium to another
  • Light bends towards the normal when entering a denser medium
• Critical Angle and Total Internal Reflection:

  • Critical angle: Angle at which light reflects entirely within a medium
  • Relationship: Sin(critical angle) = 1 / Refractive index
• Dispersion:

  • Prisms disperse light into constituent colors
  • Different colors refract at slightly different angles
• Transmission of Signals:

  • Digital signals represented by binary code (ones and zeros)
  • Digital signals are less prone to noise interference than analog signals
• Sound Waves:

  • Generated by vibrations, propagate through mediums
  • Reflection, refraction, and diffraction can occur with sound waves
• Measuring Speed of Sound:

  • Distance over time method or using an oscilloscope
• Sound Characteristics:

  • Pitch: Determined by frequency (higher frequency = higher pitch)
  • Loudness: Determined by amplitude
• Human Hearing Range:

  • Typically from 20 to 20,000 Hz, diminishing with age