MHB Determine Y of New Coordinate with -6 db/octave Slope on Log Plot

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To determine the new coordinate on a log plot with a slope of -6 dB/octave starting from the point (10^2, 100), the second coordinate at (10^3) would be (10^3, 80 dB). This is based on the understanding that a slope of -6 dB/octave translates to -20 dB/decade. Following this, if the slope changes to -12 dB/octave, the next coordinate at (10^4) would be (10^4, 60 dB). The discussion clarifies the relationship between slope and dB values across logarithmic scales. Accurate calculations are essential for determining the correct y-values at specified x-coordinates.
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On a log plot in the x axis, if I have a slope of -6 db/octave from 100db, what would be the location of the new coordinate?

So the y-axis is db and the x-axis is in log.

First coordinate is \((10^2, 100)\) then a slope of -6. The second coordinate is \((10^3, ?)\)?

How does one determine the y location?
 
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dwsmith said:
On a log plot in the x axis, if I have a slope of -6 db/octave from 100db, what would be the location of the new coordinate?

So the y-axis is db and the x-axis is in log.

First coordinate is \((10^2, 100)\) then a slope of -6. The second coordinate is \((10^3, ?)\)?

How does one determine the y location?

A slope of - 6 dB/octave is equivalent to a slope of -20 dB/decade...

Kind regards

$\chi$ $\sigma$
 
chisigma said:
A slope of - 6 dB/octave is equivalent to a slope of -20 dB/decade...

Kind regards

$\chi$ $\sigma$

Then \((10^3, 80)\), and if I had a slope of -12 following, it would be \((10^4, 40)\), correct?
 
dwsmith said:
Then \((10^3, 80)\), and if I had a slope of -12 following, it would be \((10^4, 40)\), correct?...

Not exactly... $\displaystyle (10^{3}, 80\ \text{dB})$ is correct and -20 dB\decade means $\displaystyle (10^{4}, 60\ \text{dB})$, $\displaystyle (10^{5}, 40\ \text{dB})$, etc...

Kind regards

$\chi$ $\sigma$
 
chisigma said:
Not exactly... $\displaystyle (10^{3}, 80\ \text{dB})$ is correct and -20 dB\decade means $\displaystyle (10^{4}, 60\ \text{dB})$, $\displaystyle (10^{5}, 40\ \text{dB})$, etc...

Kind regards

$\chi$ $\sigma$

You said -6 is -20 so wouldn't -12 be -40?
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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