Will a resonator change its Freq while energy is added?

In summary, the resonant frequency of a resonator can change while energy is being added or removed, depending on the nonlinearity of the real world and the presence of other modes of oscillation. Adding energy to a slightly damped oscillator may change its frequency, and coupling two oscillators together can also introduce a frequency difference and affect their frequencies.
  • #1
ctech
2
0
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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  • #2
ctech said:
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).
 
  • #3
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?
 
  • #4
ctech said:
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.
 
  • #5
ctech said:
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. :)
 
  • #6
ctech said:
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?

You say they have the same resonant frequency BUTTTTTTT, when you couple them together, you are effectively adding in another component between the two. Another mode of oscillation (a frequency difference) has been introduced. I have heard of highly stable (powered) oscillators being brought close to each other and then starting to act up by beating together, despite not being explicitly connected even. A very high Q implies minuscule power being needed to keep it going so (and a very low bandwidth). A second oscillator, with a frequency within that bandwidth, can affect it. When you say they are "in synchronisation", I think you should acknowledge that they are actually driving each other apart - if the coupling is symmetrical. If one is driving and the other is driven, the driven frequency will be pulled to that of the driver. (There is no such thing as perfect synchronisation for two independent oscillators - they will each have their own frequency.)
 

1. Will the resonant frequency of a resonator change when energy is added?

Yes, the resonant frequency of a resonator can change when energy is added. This is because the resonant frequency is determined by the physical properties of the resonator, such as its dimensions and material, and adding energy can alter these properties.

2. How does adding energy affect the resonant frequency of a resonator?

Adding energy to a resonator can alter its resonant frequency in several ways. For example, adding energy can cause the resonator to vibrate more strongly, which can change its resonant frequency. Additionally, adding energy can also change the physical properties of the resonator, such as its mass or stiffness, which can also affect the resonant frequency.

3. Is it possible for the resonant frequency to decrease when energy is added?

Yes, it is possible for the resonant frequency of a resonator to decrease when energy is added. This can occur if the added energy causes the resonator to become more flexible or lighter, which can lower its resonant frequency.

4. Can the resonant frequency of a resonator increase indefinitely when energy is continuously added?

No, the resonant frequency of a resonator cannot increase indefinitely when energy is continuously added. This is because there are physical limits to how much energy can be added and how much the resonator can change its properties. Eventually, the resonant frequency will reach a maximum value and will not increase further.

5. Will the resonant frequency of a resonator return to its original value when the added energy is removed?

In most cases, yes, the resonant frequency of a resonator will return to its original value when the added energy is removed. This is because the resonant frequency is primarily determined by the physical properties of the resonator, which will return to their original values when the added energy is removed. However, in some cases, the resonant frequency may be permanently altered due to the added energy causing damage or changes to the resonator's structure.

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