Waves in a solid practical

• Wavelength


  The distance between two consecutive peaks or troughs of a wave
• Frequency


  The number of wave cycles that pass a given point per unit of time
• Wave speed


  The speed at which the wave propagates through the medium
• Measuring wavelength, frequency and speed of waves in a solid


  1. Set up apparatus with string, vibration generator, and hanging mass

  2. Adjust signal generator to create standing wave

  3. Measure total length of standing wave

  4. Calculate wavelength by dividing total length by number of half-wavelengths and multiplying by 2

  5. Read frequency from signal generator

  6. Calculate wave speed using wave equation: wave speed = frequency x wavelength
• In the exam, students will not be required to explain how standing waves or resonance happen
• Standing waves found in


  • Stringed musical instruments (e.g. guitar)
• Increasing frequency of standing wave

  Changes standing wave pattern to have more half-wavelengths
• Wave speed does not depend on frequency or wavelength, but on the tautness of the string and mass per unit length
• In the exam, students could be shown any standing wave pattern and asked to calculate the wavelength
• Plenty of questions on this required practical are available in the revision workbook