### Description

Uses an oscillator to generate standing waves in a string. Length, string tension and driving frequency can be adjusted. Mass of string is calculated.

Outcomes:

• Observe and understand resonance.
• Observe, measure and manipulate standing waves in different harmonics.
• Understand how the principle of superposition relates to standing waves.
• Develop an understanding of the relationship between the mass and tension of a medium and the frequency, wavelength and velocity of a wave in that medium.

### Links to Stage 6 Physics Syllabus Content

PH11-10/Wave properties:

• Conduct a practical investigation involving the creation of mechanical waves in a variety of situations in order to explain:

- The role of the medium in the propagation of mechanical waves.
- The transfer of energy involved in the propagation of mechanical waves (ACSPH067, ACSPH070).

• Construct and/or interpret graphs of displacement as a function of time and as a function of position of transverse and longitudinal waves, and relate the features of those graphs to the following wave characteristics:

- Velocity
- Frequency
- Period
- Wavelength
- Displacement and amplitude (ACSPH069)

• Solve problems and/or make predictions by modelling and applying the following relationships to a variety of situations:

PH11-10/Wave Behaviour:

• Explain the behaviour of waves in a variety of situations by investigating the phenomena of:

- Reflection
- Wave superposition (ACSPH071, ACSPH072)

• Conduct an investigation to distinguish between progressive and standing waves. (ACSPH072)
• Conduct an investigation to explore resonance in mechanical systems and the relationships between:

- Driving frequency
- Natural frequency of the oscillating system
- Amplitude of motion
- Transfer/transformation of energy within the system (ACSPH073)

PH11-10/Sound waves:

• Investigate and model the behaviour of standing waves on strings and/or in pipes to relate quantitatively the fundamental and harmonic frequencies of the waves that are produced to the physical characteristics (eg length, mass, tension, wave velocity) of the medium. (ACSPH072)