Chladni figures
Principle
Square and round metal plates are brought to vibrate through acoustic stimulations by a loudspeaker. When the driving frequency corresponds to a given Eigen-frequency (natural vibration mode) of the plate, the nodal lines are made visible with sand. The sand is expelled from the vibrating regions of the plate and gathers in the lines because these are the only places where the amplitude of vibrations is close to zero.
Benefits
- Experiment set-up particularly suitable to visualize resonance
- Many experiment variations possible
- Use digital function generator for quick frequency-tuning in other experiments
PHYWE Digital Function Generator, USB
Sea sand, purified 1000
Support base, variable
Support rod, stainless steel, l = 250 mm, d = 10 mm
Boss head
Stand tube
Sound pattern plates
Loudspeaker / Sound head, 8 ohms
Connecting cord, 32 A, 500 mm, red
Connecting cord, 32 A, 500 mm, blue
Tasks
- Determine the frequencies at which resonance occurs and drive the plate specifically at these frequencies.
What you can learn about
- Wave length
- Stationary waves
- Acoustic vibrations
- Two-dimensional standing waves
- Eigen-modes