Harmonic Oscillators: Resonance Bandwidth & Frequency Range

In summary, the resonance bandwidth refers to the range of frequencies for which the average power is greater than 0.5 times the peak power. This can be shown by understanding the concept of a forced harmonic oscillator and its solution, which can be found through a simple Google search. It is important to have a basic understanding of the formulas and concepts involved in order to successfully demonstrate the resonance bandwidth criteria. It is also recommended to actively work through the problem and ask for help when needed, rather than relying on others to do the work.
  • #1
fifteenover4
2
0
Show that the resonance bandwidth corresponds to the frequency range for
which –1 < tan χ < +1. (The resonance bandwidth is the range for which the
average power is greater than 0.5 times the peak power.)


I'm pretty damn stumped with this.
 
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  • #2
Hello 4:15,
Could you use the template so that others know what this is about?
And that they can also see what ##\chi## stands for ?
And what you already know about these peak and average powers ?
 
  • #3
I've re-written it exactly as it was handed to me, hence, being stumped.

We know nothing about the peak and average powers, Ki is, I assume the impedance angle.
 
  • #4
Hello again. Still wondering if this is mechanics or electronics. Never mind, some things are universal. Google "forced harmonic oscillator" or "forced harmonic oscillator solution" to get going.

I don't feel like re-hashing the formulas. They are ubiquitous, e.g http://www.physics.oregonstate.edu/~tate/COURSES/ph421/lectures/L9.pdf (Prof. J Tate), UTexas (prof. R. Fitzpatrick), etc. etc.
Basically what you should have collected under 2. of the template.

Being stumped when confronted with something new (? isn't this in some curriculum context?) isn't good enough. Do something and get stuck somewhere; then describe the situation you are in and ask for help. You are not being helped at all if someone else does that for you. Read the guidelines.

Once you have understood the derivation and the expressions (the investment is well worth it; lasts you a lifetime) it is a piece of cake to show what is asked of you.

All this is well meant and certainly not intended offensively.
 
  • #5


I can provide an explanation for the relationship between the resonance bandwidth and the frequency range suggested in the content.

First, let's define some terms. A harmonic oscillator is a system that exhibits periodic motion, such as a pendulum or a vibrating string. Resonance is the phenomenon in which a system responds most strongly to an external force when the frequency of the force matches the natural frequency of the system. The resonance bandwidth is the range of frequencies for which the system exhibits a significant response.

Now, let's consider the expression -1 < tan χ < +1. This is the range of values for the tangent of an angle that fall between -1 and +1. In terms of resonance, this represents the angle of phase difference between the driving force and the response of the system. When the angle is between -1 and +1, it indicates that the driving force and the response are in phase, meaning they are in sync and reinforcing each other.

Now, let's connect this to the resonance bandwidth. When the driving force and the response are in phase, it means that the system is responding strongly to the force, resulting in a higher average power. This is because the force is being applied at the optimal frequency for the system. When the angle is outside of this range, the force and response are out of phase, resulting in a weaker response and lower average power.

Therefore, the resonance bandwidth, which is the range for which the average power is greater than 0.5 times the peak power, corresponds to the frequency range for which -1 < tan χ < +1. This means that for frequencies within this range, the system will exhibit a strong response and have a high average power, making it ideal for resonance. Outside of this range, the system will have a weaker response and lower average power, making it less suitable for resonance.

In conclusion, the relationship between the resonance bandwidth and the frequency range for which -1 < tan χ < +1 can be explained by the in-phase relationship between the driving force and the response of the system, resulting in a higher average power within the resonance bandwidth. I hope this explanation helps to clarify the concept of resonance and its relationship to the tangent of the phase angle.
 

FAQ: Harmonic Oscillators: Resonance Bandwidth & Frequency Range

What is a harmonic oscillator?

A harmonic oscillator is a system that exhibits periodic motion, meaning it repeats itself at regular intervals. It can be described by a mathematical function called a sinusoid, which has a specific amplitude, frequency, and phase.

What is resonance in a harmonic oscillator?

Resonance occurs in a harmonic oscillator when the frequency of an external force matches the natural frequency of the oscillator. This leads to a dramatic increase in amplitude, or the maximum displacement from the equilibrium position, and can cause the oscillator to vibrate with a large amount of energy.

What is the bandwidth of a resonance in a harmonic oscillator?

The bandwidth of a resonance in a harmonic oscillator is the range of frequencies where the oscillator will exhibit a significant response. It is determined by the quality factor, which is a measure of the sharpness of the resonance peak.

How is the frequency range of a harmonic oscillator determined?

The frequency range of a harmonic oscillator is determined by its natural frequency, which is the frequency at which it oscillates without any external forces. This can be calculated using the mass and stiffness of the oscillator, as well as any damping present in the system.

What factors affect the resonance bandwidth in a harmonic oscillator?

The resonance bandwidth in a harmonic oscillator is affected by the quality factor, which is determined by the amount of damping in the system. Higher quality factors result in narrower bandwidths, while lower quality factors result in wider bandwidths. Other factors such as mass, stiffness, and external forces can also impact the resonance bandwidth.

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