Phase

• What is amplitude in the context of waves?


  The maximum displacement of a wave from its equilibrium position
• What does superposition refer to in wave theory?


  It is the adding together of wave displacements
• What occurs when two separate sources of waves are in phase?


  They have aligned peaks and troughs, sharing the same wavelength and amplitude
• What characterizes out of phase coherent waves?


  They have peaks and troughs at a constant distance apart, maintaining the same wavelength and amplitude
• What is constructive interference in wave theory?


  • Occurs when wave crests or troughs align
  • Results in amplified amplitude
  • Waves are in phase, with zero phase difference
• What is destructive interference in wave theory?


  • Happens when a wave crest aligns with a trough
  • Results in canceling out the waves
  • Waves are out of phase, differing by half a cycle
• What type of waves are longitudinal waves?


  Waves that propagate parallel to the direction of wave propagation
• Give an example of a longitudinal wave.


  Sound waves or P waves in an earthquake
• What type of waves are transverse waves?


  Waves that propagate perpendicular to the direction of wave propagation
• Give an example of a transverse wave.


  Light waves
• What does the phase of a wave refer to?


  The position of a point on a wave relative to a fixed reference point
• How is phase measured?


  In degrees or radians
• What is the relationship between one complete cycle and phase measurement?


  One complete cycle equals 360° or $2\pi$ radians
• What are the phase angles corresponding to specific radians?


  • $3\pi/2 \text{ rad} =$$270°$
  • <latex{230° = \frac{230\pi}{180} \text{ rad}}</latex>
  • $\pi \text{ rad} =$$180°$
  • $360° \text{ or } 0° =$$2\pi \text{ rad}$
  • $90° =$$\frac{\pi}{2} \text{ rad}$