3 Oscillations and Mechanical Waves, Acoustics 3.1 Oscillatory Motion
P2150501
Chladni figures
Some Chladni figures with corresponding frequencies.
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. 1. 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
Main articles Digital Function Generator, USB, incl. Cobra4 Software Loudspeaker/Sound head Sound pattern plates Support base variable Sea sand, purified 1000 g Stand tube Boss head Support rod, stainless steel, l = 250 mm, d = 10 mm
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Function and Applications Digital signal generator for use as a programmable voltage source in practical or demonstration experiments, particularly in the disciplines of acoustics, electrical engineering and electronics Benefits
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Digital Function Generator, USB, incl. Cobra4 Software
▪ Can be used as universal stand-alone device or controlled via a USB interface ▪ Universally applicable thanks to broad, continually adjustable frequency range ▪ Usable as programmable voltage source via amplifier output ▪ Intuitive, menu-driven operation using control knob and function buttons, with help capability ▪ Illuminated monochrome graphic display for maximum visibility and readability ▪ Simple setting of voltage and frequency ramps in stand-alone mode ▪ Features V = f(f) output for easy reading of frequency in the form of a voltage - ideal for measuring circuit response to frequency ramps using an oscilloscope ▪ Low distortion and signal-to-noise ratio for brilliantly clear signals - ideal for acoustics/audio experiments 13654-99