# Will a resonator change its Freq while energy is added?

by ctech
 P: 2 Consider this, will resonator change its frequency while energy is being added or removed? Why? Should not matter if the resonator is mechanical or electrical.
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P: 7,274
 Quote by ctech Consider this, will resonator change its frequency while energy is being added or removed?
In real life, yes. In elementary physics textbooks, no.

 Why?
The real world is nonlinear. The examples in elementary textbooks usually are not, because nonlinear problems are too hard for beginners to solve.

To make an obvious comment about a real word resonator - if you add enough energy, something will break (mechanical) or burn out (electrical).
 P: 2 Thank you, So considering two tuning forks, same resonant frequency without load, coupled k~0.1 and freely swinging in synchronization. Now when one adds energy to the first tuning fork and dampen, not excessively, the second fork, they would move out of synchronization?
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P: 12,238
Will a resonator change its Freq while energy is added?

 Quote by ctech Consider this, will resonator change its frequency while energy is being added or removed? Why? Should not matter if the resonator is mechanical or electrical.
I think that, for energy to be added to a free oscillator, there must be a finite phase lead in the added signal (and vice versa). This would have the effect of producing a resultant that has a phase, different from the original oscillation. With two coupled oscillators, at any given time, one is ahead or behind the other in phase and the energy oscillates between the two at their difference frequency. So I would expect a phase modulation (AKA differentiated FM) of each oscillation at that difference frequency.
P: 835
 Quote by ctech Thank you, So considering two tuning forks, same resonant frequency without load, coupled k~0.1 and freely swinging in synchronization. Now when one adds energy to the first tuning fork and dampen, not excessively, the second fork, they would move out of synchronization?
Depends how you add energy I suppose. A slightly damped oscillator will have a slightly lowered frequency, so if you think of your energy addition as (magically) the opposite of damping, maybe it should speed up the oscillator. :)