Formation of Stationary Waves

• What is the principle of superposition?

  Resultant displacement is the sum of displacements
• How do waves interact at a point in space?

  They superpose to form a resultant wave
• What happens when two waves are in phase?

  They cause constructive interference

  
• What is the result of constructive interference?

  The resultant wave has double the amplitude

  
• What occurs during destructive interference?

  The resultant wave has no amplitude
• What types of waves does the principle of superposition apply to?

  Transverse and longitudinal waves
• What conditions are necessary for the formation of stationary waves?

  • Two waves traveling in opposite directions
  • Same frequency and wavelength
  • Similar amplitude
• What are nodes in a stationary wave?

  Points where destructive interference occurs

  
• What are antinodes in a stationary wave?

  Points where constructive interference occurs

  
• How does the amplitude of a stationary wave vary?

  Each point has a different amplitude
• How do stationary waves produce sound in stringed instruments?

  • Vibrations on a stretched string
  • Produce sound through resonant frequencies
  • Whole number of half wavelengths fit on the string
• What is the role of resonant frequencies in stationary waves on strings?

  They determine the formation of standing waves
• How are stationary waves demonstrated using microwaves?

  • Microwave source aligned with a reflecting plate
  • Detector moves to identify nodes and antinodes
  • Stationary wave pattern varies with reflector position

  
• How do stationary waves form in an air column?

  • Sound waves create stationary waves
  • Minima (nodes) at one end, maxima (antinodes) at the other
  • Demonstrated with fine powder and loudspeaker
• What is the significance of nodes and antinodes in an air column?

  Nodes indicate zero disturbance, antinodes maximum disturbance
• How does a loudspeaker contribute to the formation of stationary waves in a tube?

  It produces waves that reflect and overlap
• What should you remember when answering exam questions about stationary waves?

  • Refer back to the experiment or scenario
  • Describe wave reflection and overlap
  • Mention frequency consistency in waves