1. Vibration of membrane Chladni figures Boguslaw Lanuszny - Poland HST-2002

2. If you stretch a membrane over the ring and activate it by a speaker, you can get different shapes of modes of vibration. speaker membrane sound generator

9. Relations between frequency and shapes is given by solving the differential equation for membrane and are function of two integer: n – main quantum number (1, 2, 3…) l – second quantum number (0, 1, 2.. n-1) Theoretical and measured values of frequency are presented on next slides:

10. 123 0 1 2 n l Theoretical and experimental data

11. 123 0 k=1 f t =32 Hz f e =32 Hz k=2.3 f t =74 Hz fe=80 Hz k=3.6 f t =115 Hz f e =128 Hz 1 k=1.6 f t =51 Hz f e =54 Hz k=2.9 f t =93 Hz f e =102 Hz 2 k=2.1 f t =67 Hz f e =74 Hz n l Theoretical and experimental data