What is the meaning of FWHMP and Q in my lab data?

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In summary, During lab I obtained the data in the attached photo. It then asked for me to plot the data and get an estimated FWHMP as well as a "Q". First question is what does FWHMP and Q stand for? Second, where on my graph would I estimate these? FWHMP stands for Full Width at Half Maxima, which can be calculated using numerical programming languages. Q stands for Q factor, a parameter in the equation for the response of a simple harmonic oscillator, which determines the width of the frequency response curve. It can also be represented as ζ, the damping coefficient.
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Logan Land
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View attachment 3986

During lab I obtained the data in the attached photo.
It then asked for me to plot the data and get an estimated FWHMP as well as a "Q"
First question is what does FWHMP and Q stand for?
Second, where on my graph would I estimate these?

View attachment 3987
 

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Logan Land said:
First question is what does FWHMP and Q stand for?
Second, where on my graph would I estimate these?
Except the trailing "P", FWHM stands for Full Width at Half Maxima. Here is a good Wikipedia article about it:
https://en.wikipedia.org/wiki/Full_width_at_half_maximum

FWHM can be calculated, for instance, in MATLAB using this function file: https://www.mathworks.com/matlabcentral/fileexchange/10590-fwhm

Other programming languages that have support for numerical programming should have something related to this. FWHM is fairly common in physics.
 
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Honestly, I'm not clear on where to start discussing "Q". There are a few different equivalent interpretations of it depending on your problem or field. You can start with wikipedia https://en.wikipedia.org/wiki/Q_fac... engineering, the,of the cycle of oscillation.

It is basically a parameter in the equation for the response or behavior of a simple harmonic oscillator. In your example, it will determine the width of the frequency response curve.

If you are familiar with complex numbers, I can show you some relevant equations.

Note that when you study this, some use ζ, the damping coefficient instead of Q. Q = 1/(2⋅ζ), they represent the same concept.
 
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FAQ: What is the meaning of FWHMP and Q in my lab data?

1. What is FWHM and how is it estimated?

Full Width at Half Maximum (FWHM) is a measure of the width of a peak in a spectrum. It is estimated by finding the wavelength or frequency at which the intensity of the peak is half of its maximum value.

2. What does FWHM represent in terms of a spectrum?

FWHM represents the width of a peak at half of its maximum intensity in a spectrum. It is used to characterize the sharpness or broadness of a peak in the spectrum.

3. How is FWHM related to the resolution of a spectrum?

FWHM is directly related to the resolution of a spectrum. A smaller FWHM indicates a higher resolution, meaning that smaller differences in wavelength or frequency can be resolved in the spectrum.

4. What is Q and how is it calculated?

Q is a dimensionless quantity that represents the quality factor or sharpness of a resonant system. It is calculated by dividing the resonant frequency by the FWHM of the peak in the spectrum.

5. How does the value of Q affect the behavior of a resonant system?

A higher value of Q indicates a more stable and sharp resonant system, while a lower value of Q indicates a broader and less stable system. In practical applications, a higher Q value is desirable for better precision and sensitivity.

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