Why Do Bounded Mediums Have Specific Eigenfrequencies?

[saumya yadav]

in waves and oscillations i read that any bounded medium oscillates in a particular freuency...why is it so?i need a proper reason for this

 

[mfb]

Please post your questions in new threads, not in existing threads about other topics. I splitted the thread.

Two arguments:
- you can perform a Fourier transformation on any oscillation, and you get a set of some resonance frequencies.
- every oscillation returns to its initial state eventually (not exactly true, but good enough here). Afterwards, it just repeats again and again, if you neglect damping.

 

[saumya yadav]

what gives rise to these oscillations?thermal energy of constituting particles...?I guess.

 

[nasu]

what gives rise to these oscillations?thermal energy of constituting particles...?I guess.

This may indicate that there is some confusion regarding the meaning of
"any bounded medium oscillates in a particular frequency"

"Oscillates" here does not mean that it spontaneously oscillates.
If you "excite" the medium somehow, this will induce oscillations (or waves).